Example #1
0
def bql_pdf_joint(bdb, generator_id, modelno, *args):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    # A nonexistent (`unobserved') row id.
    fake_row_id = core.bayesdb_generator_fresh_row_id(bdb, generator_id)
    i = 0
    targets = []
    while i < len(args):
        if args[i] == -1:
            i += 1
            break
        if i + 1 == len(args):
            raise ValueError('Missing logpdf target value: %r' % (args[i],))
        t_colno = args[i]
        t_value = args[i + 1]
        targets.append((fake_row_id, t_colno, t_value))
        i += 2
    constraints = []
    while i < len(args):
        if i + 1 == len(args):
            raise ValueError('Missing logpdf constraint value: %r' %
                (args[i],))
        c_colno = args[i]
        c_value = args[i + 1]
        constraints.append((fake_row_id, c_colno, c_value))
        i += 2
    logp = metamodel.logpdf_joint(bdb, generator_id, targets, constraints,
        modelno)
    return ieee_exp(logp)
Example #2
0
def _bql_logpdf(bdb, population_id, generator_id, targets, constraints):
    # P(T | C) = \sum_M P(T, M | C)
    # = \sum_M P(T | C, M) P(M | C)
    # = \sum_M P(T | C, M) P(M) P(C | M) / P(C)
    # = \sum_M P(T | C, M) P(M) P(C | M) / \sum_M' P(C, M')
    # = \sum_M P(T | C, M) P(M) P(C | M) / \sum_M' P(C | M') P(M')
    #
    # For a generator M, logpdf(M) computes P(T | C, M), and
    # loglikelihood(M) computes P(C | M).  For now, we weigh each
    # generator uniformly; eventually, we ought to allow the user to
    # specify a prior weight (XXX and update some kind of posterior
    # weight?).
    rowid, constraints = _retrieve_rowid_constraints(bdb, population_id,
                                                     constraints)

    def logpdf(generator_id, metamodel):
        return metamodel.logpdf_joint(bdb, generator_id, rowid, targets,
                                      constraints, None)

    def loglikelihood(generator_id, metamodel):
        if not constraints:
            return 0
        return metamodel.logpdf_joint(bdb, generator_id, rowid, constraints,
                                      [], None)

    generator_ids = _retrieve_generator_ids(bdb, population_id, generator_id)
    metamodels = [
        core.bayesdb_generator_metamodel(bdb, g) for g in generator_ids
    ]
    loglikelihoods = map(loglikelihood, generator_ids, metamodels)
    logpdfs = map(logpdf, generator_ids, metamodels)
    return logavgexp_weighted(loglikelihoods, logpdfs)
Example #3
0
 def generator_similarity(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     # XXX Change [colno] to colno by updating IBayesDBMetamodel.
     similarity_list = metamodel.row_similarity(bdb, generator_id, modelnos,
                                                rowid, target_rowid,
                                                [colno])
     return stats.arithmetic_mean(similarity_list)
Example #4
0
def bql_predict_confidence(bdb, generator_id, modelno, colno, rowid,
        numsamples=None):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    value, confidence = metamodel.predict_confidence(bdb, generator_id,
        modelno, colno, rowid, numsamples=numsamples)
    # XXX Whattakludge!
    return json.dumps({'value': value, 'confidence': confidence})
Example #5
0
def bayesdb_simulate(bdb,
                     generator_id,
                     constraints,
                     colnos,
                     modelno=None,
                     numpredictions=1):
    """Simulate rows from a generative model, subject to constraints.

    Returns a list of `numpredictions` tuples, with a value for each
    column specified in the list `colnos`, conditioned on the
    constraints in the list `constraints` of tuples ``(colno,
    value)``.

    The results are simulated from the predictive distribution on
    fresh rows.

    """
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    fake_rowid = core.bayesdb_generator_fresh_row_id(bdb, generator_id)
    targets = [(fake_rowid, colno) for colno in colnos]
    if constraints is not None:
        constraints = [(fake_rowid, colno, val) for colno, val in constraints]
    return metamodel.simulate_joint(bdb,
                                    generator_id,
                                    targets,
                                    constraints,
                                    modelno,
                                    num_predictions=numpredictions)
Example #6
0
def bql_pdf_joint(bdb, generator_id, modelno, *args):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    # A nonexistent (`unobserved') row id.
    fake_row_id = core.bayesdb_generator_fresh_row_id(bdb, generator_id)
    i = 0
    targets = []
    while i < len(args):
        if args[i] == -1:
            i += 1
            break
        if i + 1 == len(args):
            raise ValueError('Missing logpdf target value: %r' % (args[i], ))
        t_colno = args[i]
        t_value = args[i + 1]
        targets.append((fake_row_id, t_colno, t_value))
        i += 2
    constraints = []
    while i < len(args):
        if i + 1 == len(args):
            raise ValueError('Missing logpdf constraint value: %r' %
                             (args[i], ))
        c_colno = args[i]
        c_value = args[i + 1]
        constraints.append((fake_row_id, c_colno, c_value))
        i += 2
    logp = metamodel.logpdf_joint(bdb, generator_id, targets, constraints,
                                  modelno)
    return ieee_exp(logp)
Example #7
0
def bql_predict_confidence(bdb, generator_id, modelno, colno, rowid,
        numsamples=None):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    value, confidence = metamodel.predict_confidence(bdb, generator_id,
        modelno, colno, rowid, numsamples=numsamples)
    # XXX Whattakludge!
    return json.dumps({'value': value, 'confidence': confidence})
Example #8
0
def bayesdb_simulate(bdb, population_id, constraints, colnos,
        generator_id=None, numpredictions=1, accuracy=None):
    """Simulate rows from a generative model, subject to constraints.

    Returns a list of `numpredictions` tuples, with a value for each
    column specified in the list `colnos`, conditioned on the
    constraints in the list `constraints` of tuples ``(colno,
    value)``.

    The results are simulated from the predictive distribution on
    fresh rows.
    """
    rowid = core.bayesdb_population_fresh_row_id(bdb, population_id)
    if constraints is not None:
        user_rowid = [
            v for c, v in constraints
            if c in core.bayesdb_rowid_tokens(bdb)
        ]
        if len(user_rowid) == 1:
            rowid = user_rowid[0]
        elif len(user_rowid) > 1:
            raise BQLError(bdb, 'Multiple rowids given: %s.' % (constraints,))
        constraints = [
            (rowid, c, v) for c, v in constraints
            if c not in core.bayesdb_rowid_tokens(bdb)
        ]
    targets = [(rowid, colno) for colno in colnos]
    def loglikelihood(generator_id, metamodel):
        if not constraints:
            return 0
        return metamodel.logpdf_joint(
            bdb, generator_id, constraints, [], None)
    def simulate(generator_id, metamodel, n):
        return metamodel.simulate_joint(
            bdb, generator_id, targets,
            constraints, None, num_predictions=n, accuracy=accuracy)
    generator_ids = [generator_id] if generator_id is not None else \
        core.bayesdb_population_generators(bdb, population_id)
    metamodels = [core.bayesdb_generator_metamodel(bdb, generator_id)
        for generator_id in generator_ids]
    if len(generator_ids) > 1:
        loglikelihoods = map(loglikelihood, generator_ids, metamodels)
        likelihoods = map(math.exp, loglikelihoods)
        total_likelihood = sum(likelihoods)
        if total_likelihood == 0:
            # XXX Show the constraints with symbolic names.
            raise BQLError(bdb, 'Impossible constraints: %r' % (constraints,))
        probabilities = [likelihood/total_likelihood
            for likelihood in likelihoods]
        countses = bdb.np_prng.multinomial(
            numpredictions, probabilities, size=1)
        counts = countses[0]
    else:
        counts = [numpredictions]
    rowses = map(simulate, generator_ids, metamodels, counts)
    all_rows = [row for rows in rowses for row in rows]
    assert all(isinstance(row, (tuple, list)) for row in all_rows)
    return all_rows
Example #9
0
 def generator_mutinf(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     return metamodel.column_mutual_information(bdb,
                                                generator_id,
                                                None,
                                                colnos0,
                                                colnos1,
                                                constraints=constraints,
                                                numsamples=numsamples)
Example #10
0
def bql_row_similarity(bdb, generator_id, modelno, rowid, target_rowid,
                       *colnos):
    if target_rowid is None:
        raise BQLError(bdb, 'No such target row for SIMILARITY')
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    if len(colnos) == 0:
        colnos = core.bayesdb_generator_column_numbers(bdb, generator_id)
    return metamodel.row_similarity(bdb, generator_id, modelno, rowid,
                                    target_rowid, colnos)
Example #11
0
def bql_row_column_predictive_probability(bdb, generator_id, modelno, rowid,
                                          colno):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    value = core.bayesdb_generator_cell_value(bdb, generator_id, rowid, colno)
    if value is None:
        return None
    r = metamodel.logpdf_joint(bdb, generator_id, [(rowid, colno, value)], [],
                               modelno)
    return ieee_exp(r)
Example #12
0
def bql_row_similarity(bdb, generator_id, modelno, rowid, target_rowid,
        *colnos):
    if target_rowid is None:
        raise BQLError(bdb, 'No such target row for SIMILARITY')
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    if len(colnos) == 0:
        colnos = core.bayesdb_generator_column_numbers(bdb, generator_id)
    return metamodel.row_similarity(bdb, generator_id, modelno, rowid,
        target_rowid, colnos)
Example #13
0
def bql_row_column_predictive_probability(bdb, generator_id, modelno, rowid,
        colno):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    value = core.bayesdb_generator_cell_value(
        bdb, generator_id, rowid, colno)
    if value is None:
        return None
    r = metamodel.logpdf_joint(
        bdb, generator_id, [(rowid, colno, value)], [], modelno)
    return ieee_exp(r)
Example #14
0
def bql_predict(bdb, population_id, generator_id, colno, rowid, threshold,
        numsamples):
    # XXX Randomly sample 1 generator from the population, until we figure out
    # how to aggregate imputations across different hypotheses.
    if generator_id is None:
        generator_ids = core.bayesdb_population_generators(bdb, population_id)
        index = bdb.np_prng.randint(0, high=len(generator_ids))
        generator_id = generator_ids[index]
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    return metamodel.predict(bdb, generator_id, None, colno, rowid,
        threshold, numsamples=numsamples)
Example #15
0
def bayesdb_simulate(
        bdb, population_id, generator_id, modelnos, constraints, colnos,
        numpredictions=1, accuracy=None):
    """Simulate rows from a generative model, subject to constraints.

    Returns a list of `numpredictions` tuples, with a value for each
    column specified in the list `colnos`, conditioned on the
    constraints in the list `constraints` of tuples ``(colno,
    value)``.

    The results are simulated from the predictive distribution on
    fresh rows.
    """
    modelnos = _retrieve_modelnos(modelnos)
    rowid, constraints = _retrieve_rowid_constraints(
        bdb, population_id, constraints)
    def loglikelihood(generator_id, metamodel):
        if not constraints:
            return 0
        return metamodel.logpdf_joint(
            bdb, generator_id, modelnos, rowid, constraints, [])
    def simulate(generator_id, metamodel, n):
        return metamodel.simulate_joint(
            bdb, generator_id, modelnos, rowid, colnos, constraints,
            num_samples=n, accuracy=accuracy)
    generator_ids = _retrieve_generator_ids(bdb, population_id, generator_id)
    metamodels = [
        core.bayesdb_generator_metamodel(bdb, generator_id)
        for generator_id in generator_ids
    ]
    if len(generator_ids) > 1:
        loglikelihoods = map(loglikelihood, generator_ids, metamodels)
        likelihoods = map(math.exp, loglikelihoods)
        total_likelihood = sum(likelihoods)
        if total_likelihood == 0:
            # XXX Show the constraints with symbolic names.
            raise BQLError(bdb, 'Impossible constraints: %r' % (constraints,))
        probabilities = [
            likelihood / total_likelihood
            for likelihood in likelihoods
        ]
        countses = bdb.np_prng.multinomial(
            numpredictions, probabilities, size=1)
        counts = countses[0]
    elif len(generator_ids) == 1:
        counts = [numpredictions]
    else:
        counts = []
    rowses = map(simulate, generator_ids, metamodels, counts)
    all_rows = [row for rows in rowses for row in rows]
    assert all(isinstance(row, (tuple, list)) for row in all_rows)
    return all_rows
Example #16
0
def bql_column_mutual_information(bdb,
                                  generator_id,
                                  modelno,
                                  colno0,
                                  colno1,
                                  numsamples=None):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    return metamodel.column_mutual_information(bdb,
                                               generator_id,
                                               modelno,
                                               colno0,
                                               colno1,
                                               numsamples=numsamples)
Example #17
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def bql_predict_confidence(bdb, population_id, generator_id, colno, rowid,
        numsamples):
    # XXX Do real imputation here!
    # XXX Randomly sample 1 generator from the population, until we figure out
    # how to aggregate imputations across different hypotheses.
    if generator_id is None:
        generator_ids = core.bayesdb_population_generators(bdb, population_id)
        index = bdb.np_prng.randint(0, high=len(generator_ids))
        generator_id = generator_ids[index]
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    value, confidence = metamodel.predict_confidence(bdb, generator_id,
        None, colno, rowid, numsamples=numsamples)
    # XXX Whattakludge!
    return json.dumps({'value': value, 'confidence': confidence})
Example #18
0
def bql_predict(bdb,
                generator_id,
                modelno,
                colno,
                rowid,
                threshold,
                numsamples=None):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    return metamodel.predict(bdb,
                             generator_id,
                             modelno,
                             colno,
                             rowid,
                             threshold,
                             numsamples=numsamples)
Example #19
0
def bql_column_value_probability(bdb, generator_id, modelno, colno, value,
                                 *constraint_args):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    # A nonexistent (`unobserved') row id.
    fake_row_id = core.bayesdb_generator_fresh_row_id(bdb, generator_id)
    constraints = []
    i = 0
    while i < len(constraint_args):
        if i + 1 == len(constraint_args):
            raise ValueError('Odd constraint arguments: %s' %
                             (constraint_args, ))
        constraint_colno = constraint_args[i]
        constraint_value = constraint_args[i + 1]
        constraints.append((fake_row_id, constraint_colno, constraint_value))
        i += 2
    targets = [(fake_row_id, colno, value)]
    r = metamodel.logpdf_joint(bdb, generator_id, targets, constraints,
                               modelno)
    return ieee_exp(r)
Example #20
0
def bql_column_value_probability(bdb, generator_id, modelno, colno, value,
        *constraint_args):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    # A nonexistent (`unobserved') row id.
    fake_row_id = core.bayesdb_generator_fresh_row_id(bdb, generator_id)
    constraints = []
    i = 0
    while i < len(constraint_args):
        if i + 1 == len(constraint_args):
            raise ValueError('Odd constraint arguments: %s' %
                (constraint_args,))
        constraint_colno = constraint_args[i]
        constraint_value = constraint_args[i + 1]
        constraints.append((fake_row_id, constraint_colno, constraint_value))
        i += 2
    targets = [(fake_row_id, colno, value)]
    r = metamodel.logpdf_joint(
        bdb, generator_id, targets, constraints, modelno)
    return ieee_exp(r)
Example #21
0
def bayesdb_simulate(bdb, generator_id, constraints, colnos,
        modelno=None, numpredictions=1):
    """Simulate rows from a generative model, subject to constraints.

    Returns a list of `numpredictions` tuples, with a value for each
    column specified in the list `colnos`, conditioned on the
    constraints in the list `constraints` of tuples ``(colno,
    value)``.

    The results are simulated from the predictive distribution on
    fresh rows.

    """
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    fake_rowid = core.bayesdb_generator_fresh_row_id(bdb, generator_id)
    targets = [(fake_rowid, colno) for colno in colnos]
    if constraints is not None:
        constraints = [(fake_rowid, colno, val)
                       for colno, val in constraints]
    return metamodel.simulate_joint(bdb, generator_id, targets,
        constraints, modelno, num_predictions=numpredictions)
Example #22
0
 def generator_similarity(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     return metamodel.predictive_relevance(bdb, generator_id, modelnos,
                                           rowid_target, rowid_query,
                                           hypotheticals, colno)
Example #23
0
def bql_column_dependence_probability(bdb, generator_id, modelno, colno0,
        colno1):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    return metamodel.column_dependence_probability(bdb, generator_id, modelno,
        colno0, colno1)
Example #24
0
def bql_column_dependence_probability(bdb, generator_id, modelno, colno0,
                                      colno1):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    return metamodel.column_dependence_probability(bdb, generator_id, modelno,
                                                   colno0, colno1)
Example #25
0
 def generator_predprob(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     return metamodel.logpdf_joint(bdb, generator_id, fresh_rowid, query,
                                   constraints, None)
Example #26
0
 def generator_similarity(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     return metamodel.row_similarity(bdb, generator_id, None, rowid,
                                     target_rowid, colnos)
Example #27
0
def execute_phrase(bdb, phrase, bindings=()):
    """Execute the BQL AST phrase `phrase` and return a cursor of results."""
    if isinstance(phrase, ast.Parametrized):
        n_numpar = phrase.n_numpar
        nampar_map = phrase.nampar_map
        phrase = phrase.phrase
        assert 0 < n_numpar
    else:
        n_numpar = 0
        nampar_map = None
        # Ignore extraneous bindings.  XXX Bad idea?

    if ast.is_query(phrase):
        # Compile the query in the transaction in case we need to
        # execute subqueries to determine column lists.  Compiling is
        # a quick tree descent, so this should be fast.
        out = compiler.Output(n_numpar, nampar_map, bindings)
        with bdb.savepoint():
            compiler.compile_query(bdb, phrase, out)
        winders, unwinders = out.getwindings()
        return execute_wound(bdb, winders, unwinders, out.getvalue(),
                             out.getbindings())

    if isinstance(phrase, ast.Begin):
        txn.bayesdb_begin_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Rollback):
        txn.bayesdb_rollback_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Commit):
        txn.bayesdb_commit_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabAs):
        assert ast.is_query(phrase.query)
        with bdb.savepoint():
            if core.bayesdb_has_table(bdb, phrase.name):
                if phrase.ifnotexists:
                    return empty_cursor(bdb)
                else:
                    raise BQLError(
                        bdb, 'Name already defined as table: %s' %
                        (repr(phrase.name), ))
            out = compiler.Output(n_numpar, nampar_map, bindings)
            qt = sqlite3_quote_name(phrase.name)
            temp = 'TEMP ' if phrase.temp else ''
            ifnotexists = 'IF NOT EXISTS ' if phrase.ifnotexists else ''
            out.write('CREATE %sTABLE %s%s AS ' % (temp, ifnotexists, qt))
            compiler.compile_query(bdb, phrase.query, out)
            winders, unwinders = out.getwindings()
            with compiler.bayesdb_wind(bdb, winders, unwinders):
                bdb.sql_execute(out.getvalue(), out.getbindings())
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabCsv):
        with bdb.savepoint():
            table_exists = core.bayesdb_has_table(bdb, phrase.name)
            if table_exists:
                if phrase.ifnotexists:
                    return empty_cursor(bdb)
                else:
                    raise BQLError(
                        bdb,
                        'Table already exists: %s' % (repr(phrase.name), ))
            bayesdb_read_csv_file(bdb,
                                  phrase.name,
                                  phrase.csv,
                                  header=True,
                                  create=True)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabSimModels):
        assert isinstance(phrase.simulation, ast.SimulateModels)
        with bdb.savepoint():
            # Check if table exists.
            if core.bayesdb_has_table(bdb, phrase.name):
                if phrase.ifnotexists:
                    return empty_cursor(bdb)
                raise BQLError(
                    bdb,
                    'Name already defined as table: %s' % (phrase.name),
                )
            # Set up schema and create the new table.
            qn = sqlite3_quote_name(phrase.name)
            qcns = map(sqlite3_quote_name, [
                simcol.name if simcol.name is not None else str(simcol.col)
                for simcol in phrase.simulation.columns
            ])
            temp = '' if phrase.temp is None else 'TEMP'
            bdb.sql_execute('''
                CREATE %s TABLE %s (%s)
            ''' % (temp, qn, str.join(',', qcns)))
            # Retrieve the rows.
            rows = simulate_models_rows(bdb, phrase.simulation)
            # Insert the rows into the table.
            insert_sql = '''
                INSERT INTO %s (%s) VALUES (%s)
            ''' % (qn, ','.join(qcns), ','.join('?' for qcn in qcns))
            for row in rows:
                bdb.sql_execute(insert_sql, row)
            return empty_cursor(bdb)

    if isinstance(phrase, ast.DropTab):
        with bdb.savepoint():
            sql = 'SELECT COUNT(*) FROM bayesdb_population WHERE tabname = ?'
            cursor = bdb.sql_execute(sql, (phrase.name, ))
            if 0 < cursor_value(cursor):
                raise BQLError(
                    bdb, 'Table still in use by populations: %s' %
                    (repr(phrase.name), ))
            bdb.sql_execute('DELETE FROM bayesdb_column WHERE tabname = ?',
                            (phrase.name, ))
            ifexists = 'IF EXISTS ' if phrase.ifexists else ''
            qt = sqlite3_quote_name(phrase.name)
            return bdb.sql_execute('DROP TABLE %s%s' % (ifexists, qt))

    if isinstance(phrase, ast.AlterTab):
        with bdb.savepoint():
            table = phrase.table
            if not core.bayesdb_has_table(bdb, table):
                raise BQLError(bdb, 'No such table: %s' % (repr(table), ))
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterTabRenameTab):
                    # If the names differ only in case, we have to do
                    # some extra work because SQLite will reject the
                    # table rename.  Note that we may even have table
                    # == cmd.name here, but if the stored table name
                    # differs in case from cmd.name, we want to update
                    # it anyway.
                    if casefold(table) == casefold(cmd.name):
                        # Go via a temporary table.
                        temp = table + '_temp'
                        while core.bayesdb_has_table(bdb, temp):
                            temp += '_temp'
                        rename_table(bdb, table, temp)
                        rename_table(bdb, temp, cmd.name)
                    else:
                        # Make sure nothing else has this name and
                        # rename it.
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined as table'
                                ': %s' % (repr(cmd.name), ))
                        rename_table(bdb, table, cmd.name)
                    # Remember the new name for subsequent commands.
                    table = cmd.name
                elif isinstance(cmd, ast.AlterTabRenameCol):
                    # XXX Need to deal with this in the compiler.
                    raise NotImplementedError('Renaming columns'
                                              ' not yet implemented.')
                    # Make sure the old name exist and the new name does not.
                    old_folded = casefold(cmd.old)
                    new_folded = casefold(cmd.new)
                    if old_folded != new_folded:
                        if not core.bayesdb_table_has_column(
                                bdb, table, cmd.old):
                            raise BQLError(
                                bdb, 'No such column in table %s'
                                ': %s' % (repr(table), repr(cmd.old)))
                        if core.bayesdb_table_has_column(bdb, table, cmd.new):
                            raise BQLError(
                                bdb, 'Column already exists'
                                ' in table %s: %s' %
                                (repr(table), repr(cmd.new)))
                    # Update bayesdb_column.  Everything else refers
                    # to columns by (tabname, colno) pairs rather than
                    # by names.
                    update_column_sql = '''
                        UPDATE bayesdb_column SET name = :new
                            WHERE tabname = :table AND name = :old
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(update_column_sql, {
                        'table': table,
                        'old': cmd.old,
                        'new': cmd.new,
                    })
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                    # ...except metamodels may have the (case-folded)
                    # name cached.
                    if old_folded != new_folded:
                        generators_sql = '''
                            SELECT id FROM bayesdb_generator WHERE tabname = ?
                        '''
                        cursor = bdb.sql_execute(generators_sql, (table, ))
                        for (generator_id, ) in cursor:
                            metamodel = core.bayesdb_generator_metamodel(
                                bdb, generator_id)
                            metamodel.rename_column(bdb, generator_id,
                                                    old_folded, new_folded)
                else:
                    assert False, 'Invalid alter table command: %s' % \
                        (cmd,)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.GuessSchema):
        if not core.bayesdb_has_table(bdb, phrase.table):
            raise BQLError(bdb, 'No such table : %s' % phrase.table)
        schema = guess.guess_to_schema(guess.bayesdb_guess_stattypes, bdb,
                                       phrase.table)
        # Print schema to console, so user can edit it and/or copy/paste it into
        # the schema definition when creating a population.
        print schema
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreatePop):
        with bdb.savepoint():
            _create_population(bdb, phrase)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropPop):
        with bdb.savepoint():
            if not core.bayesdb_has_population(bdb, phrase.name):
                if phrase.ifexists:
                    return empty_cursor(bdb)
                raise BQLError(bdb, 'No such population: %r' % (phrase.name, ))
            population_id = core.bayesdb_get_population(bdb, phrase.name)
            if core.bayesdb_population_generators(bdb, population_id):
                raise BQLError(
                    bdb,
                    'Population still has generators: %r' % (phrase.name, ))
            # XXX helpful error checking if generators still exist
            # XXX check change counts
            bdb.sql_execute(
                '''
                DELETE FROM bayesdb_variable WHERE population_id = ?
            ''', (population_id, ))
            bdb.sql_execute(
                '''
                DELETE FROM bayesdb_population WHERE id = ?
            ''', (population_id, ))
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AlterPop):
        with bdb.savepoint():
            population = phrase.population
            if not core.bayesdb_has_population(bdb, population):
                raise BQLError(bdb,
                               'No such population: %s' % (repr(population), ))
            population_id = core.bayesdb_get_population(bdb, population)
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterPopStatType):
                    # Check the no metamodels are defined for this population.
                    generators = core.bayesdb_population_generators(
                        bdb, population_id)
                    if generators:
                        raise BQLError(
                            bdb, 'Cannot update statistical types '
                            'for population %s, it has metamodels: %s' % (
                                repr(population),
                                repr(generators),
                            ))
                    # Check all the variables are in the population.
                    unknown = [
                        c for c in cmd.names if not core.bayesdb_has_variable(
                            bdb, population_id, None, c)
                    ]
                    if unknown:
                        raise BQLError(
                            bdb, 'No such variables in population'
                            ': %s' % (repr(unknown)))
                    # Check the statistical type is valid.
                    if not core.bayesdb_has_stattype(bdb, cmd.stattype):
                        raise BQLError(
                            bdb, 'Invalid statistical type'
                            ': %r' % (repr(cmd.stattype), ))
                    # Perform the stattype update.
                    colnos = [
                        core.bayesdb_variable_number(bdb, population_id, None,
                                                     c) for c in cmd.names
                    ]
                    qcolnos = ','.join('%d' % (colno, ) for colno in colnos)
                    update_stattype_sql = '''
                        UPDATE bayesdb_variable SET stattype = ?
                            WHERE population_id = ? AND colno IN (%s)
                    ''' % (qcolnos, )
                    bdb.sql_execute(update_stattype_sql, (
                        casefold(cmd.stattype),
                        population_id,
                    ))
                else:
                    assert False, 'Invalid ALTER POPULATION command: %s' % \
                        (repr(cmd),)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateGen):
        # Find the population.
        if not core.bayesdb_has_population(bdb, phrase.population):
            raise BQLError(bdb,
                           'No such population: %r' % (phrase.population, ))
        population_id = core.bayesdb_get_population(bdb, phrase.population)
        table = core.bayesdb_population_table(bdb, population_id)

        # Find the metamodel, or use the default.
        metamodel_name = phrase.metamodel
        if phrase.metamodel is None:
            metamodel_name = 'cgpm'
        if metamodel_name not in bdb.metamodels:
            raise BQLError(bdb,
                           'No such metamodel: %s' % (repr(metamodel_name), ))
        metamodel = bdb.metamodels[metamodel_name]

        with bdb.savepoint():
            if core.bayesdb_has_generator(bdb, population_id, phrase.name):
                if not phrase.ifnotexists:
                    raise BQLError(
                        bdb, 'Name already defined as generator: %s' %
                        (repr(phrase.name), ))
            else:
                # Insert a record into bayesdb_generator and get the
                # assigned id.
                bdb.sql_execute(
                    '''
                    INSERT INTO bayesdb_generator
                        (name, tabname, population_id, metamodel)
                        VALUES (?, ?, ?, ?)
                ''', (phrase.name, table, population_id, metamodel.name()))
                generator_id = core.bayesdb_get_generator(
                    bdb, population_id, phrase.name)

                # Populate bayesdb_generator_column.
                #
                # XXX Omit needless bayesdb_generator_column table --
                # Github issue #441.
                bdb.sql_execute(
                    '''
                    INSERT INTO bayesdb_generator_column
                        (generator_id, colno, stattype)
                        SELECT :generator_id, colno, stattype
                            FROM bayesdb_variable
                            WHERE population_id = :population_id
                                AND generator_id IS NULL
                ''', {
                        'generator_id': generator_id,
                        'population_id': population_id,
                    })

                # Do any metamodel-specific initialization.
                metamodel.create_generator(bdb,
                                           generator_id,
                                           phrase.schema,
                                           baseline=phrase.baseline)

                # Populate bayesdb_generator_column with any latent
                # variables that metamodel.create_generator has added
                # with bayesdb_add_latent.
                bdb.sql_execute(
                    '''
                    INSERT INTO bayesdb_generator_column
                        (generator_id, colno, stattype)
                        SELECT :generator_id, colno, stattype
                            FROM bayesdb_variable
                            WHERE population_id = :population_id
                                AND generator_id = :generator_id
                ''', {
                        'generator_id': generator_id,
                        'population_id': population_id,
                    })

        # All done.  Nothing to return.
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropGen):
        with bdb.savepoint():
            if not core.bayesdb_has_generator(bdb, None, phrase.name):
                if phrase.ifexists:
                    return empty_cursor(bdb)
                raise BQLError(bdb,
                               'No such generator: %s' % (repr(phrase.name), ))
            generator_id = core.bayesdb_get_generator(bdb, None, phrase.name)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)

            # Metamodel-specific destruction.
            metamodel.drop_generator(bdb, generator_id)

            # Drop the columns, models, and, finally, generator.
            drop_columns_sql = '''
                DELETE FROM bayesdb_generator_column WHERE generator_id = ?
            '''
            bdb.sql_execute(drop_columns_sql, (generator_id, ))
            drop_model_sql = '''
                DELETE FROM bayesdb_generator_model WHERE generator_id = ?
            '''
            bdb.sql_execute(drop_model_sql, (generator_id, ))
            drop_generator_sql = '''
                DELETE FROM bayesdb_generator WHERE id = ?
            '''
            bdb.sql_execute(drop_generator_sql, (generator_id, ))
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AlterGen):
        with bdb.savepoint():
            generator = phrase.generator
            if not core.bayesdb_has_generator(bdb, None, generator):
                raise BQLError(bdb,
                               'No such generator: %s' % (repr(generator), ))
            generator_id = core.bayesdb_get_generator(bdb, None, generator)
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterGenRenameGen):
                    # Make sure nothing else has this name.
                    if casefold(generator) != casefold(cmd.name):
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined as table'
                                ': %s' % (repr(cmd.name), ))
                        if core.bayesdb_has_generator(bdb, None, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined'
                                ' as generator: %s' % (repr(cmd.name), ))
                    # Update bayesdb_generator.  Everything else
                    # refers to it by id.
                    update_generator_sql = '''
                        UPDATE bayesdb_generator SET name = ? WHERE id = ?
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(update_generator_sql,
                                    (cmd.name, generator_id))
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                    # Remember the new name for subsequent commands.
                    generator = cmd.name
                else:
                    assert False, 'Invalid ALTER GENERATOR command: %s' % \
                        (repr(cmd),)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.InitModels):
        if not core.bayesdb_has_generator(bdb, None, phrase.generator):
            raise BQLError(bdb, 'No such generator: %s' % (phrase.generator, ))
        generator_id = core.bayesdb_get_generator(bdb, None, phrase.generator)
        modelnos = range(phrase.nmodels)

        with bdb.savepoint():
            # Find the model numbers.  Omit existing ones for
            # ifnotexists; reject existing ones otherwise.
            if phrase.ifnotexists:
                modelnos = set(modelno for modelno in modelnos
                               if not core.bayesdb_generator_has_model(
                                   bdb, generator_id, modelno))
            else:
                existing = set(modelno for modelno in modelnos
                               if core.bayesdb_generator_has_model(
                                   bdb, generator_id, modelno))
                if 0 < len(existing):
                    raise BQLError(
                        bdb, 'Generator %s already has models: %s' %
                        (repr(phrase.generator), sorted(existing)))

            # Stop now if there's nothing to initialize.
            if len(modelnos) == 0:
                return

            # Create the bayesdb_generator_model records.
            modelnos = sorted(modelnos)
            insert_model_sql = '''
                INSERT INTO bayesdb_generator_model
                    (generator_id, modelno, iterations)
                    VALUES (:generator_id, :modelno, :iterations)
            '''
            for modelno in modelnos:
                bdb.sql_execute(
                    insert_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                        'iterations': 0,
                    })

            # Do metamodel-specific initialization.
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            metamodel.initialize_models(bdb, generator_id, modelnos)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AnalyzeModels):
        if not phrase.wait:
            raise NotImplementedError('No background analysis -- use WAIT.')
        # WARNING: It is the metamodel's responsibility to work in a
        # transaction.
        #
        # WARNING: It is the metamodel's responsibility to update the
        # iteration count in bayesdb_generator_model records.
        #
        # We do this so that the metamodel can save incremental
        # progress in case of ^C in the middle.
        #
        # XXX Put these warning somewhere more appropriate.
        if not core.bayesdb_has_generator(bdb, None, phrase.generator):
            raise BQLError(bdb, 'No such generator: %s' % (phrase.generator, ))
        generator_id = core.bayesdb_get_generator(bdb, None, phrase.generator)
        metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
        # XXX Should allow parameters for iterations and ckpt/iter.
        metamodel.analyze_models(bdb,
                                 generator_id,
                                 modelnos=phrase.modelnos,
                                 iterations=phrase.iterations,
                                 max_seconds=phrase.seconds,
                                 ckpt_iterations=phrase.ckpt_iterations,
                                 ckpt_seconds=phrase.ckpt_seconds,
                                 program=phrase.program)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropModels):
        with bdb.savepoint():
            generator_id = core.bayesdb_get_generator(bdb, None,
                                                      phrase.generator)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            modelnos = None
            if phrase.modelnos is not None:
                lookup_model_sql = '''
                    SELECT COUNT(*) FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                '''
                modelnos = sorted(list(phrase.modelnos))
                for modelno in modelnos:
                    cursor = bdb.sql_execute(lookup_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                    })
                    if cursor_value(cursor) == 0:
                        raise BQLError(
                            bdb, 'No such model'
                            ' in generator %s: %s' %
                            (repr(phrase.generator), repr(modelno)))
            metamodel.drop_models(bdb, generator_id, modelnos=modelnos)
            if modelnos is None:
                drop_models_sql = '''
                    DELETE FROM bayesdb_generator_model WHERE generator_id = ?
                '''
                bdb.sql_execute(drop_models_sql, (generator_id, ))
            else:
                drop_model_sql = '''
                    DELETE FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                '''
                for modelno in modelnos:
                    bdb.sql_execute(drop_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                    })
        return empty_cursor(bdb)

    assert False  # XXX
Example #28
0
def execute_phrase(bdb, phrase, bindings=()):
    """Execute the BQL AST phrase `phrase` and return a cursor of results."""
    if isinstance(phrase, ast.Parametrized):
        n_numpar = phrase.n_numpar
        nampar_map = phrase.nampar_map
        phrase = phrase.phrase
        assert 0 < n_numpar
    else:
        n_numpar = 0
        nampar_map = None
        # Ignore extraneous bindings.  XXX Bad idea?

    if ast.is_query(phrase):
        # Compile the query in the transaction in case we need to
        # execute subqueries to determine column lists.  Compiling is
        # a quick tree descent, so this should be fast.
        out = compiler.Output(n_numpar, nampar_map, bindings)
        with bdb.savepoint():
            compiler.compile_query(bdb, phrase, out)
        winders, unwinders = out.getwindings()
        return execute_wound(bdb, winders, unwinders, out.getvalue(), out.getbindings())

    if isinstance(phrase, ast.Begin):
        txn.bayesdb_begin_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Rollback):
        txn.bayesdb_rollback_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Commit):
        txn.bayesdb_commit_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabAs):
        assert ast.is_query(phrase.query)
        with bdb.savepoint():
            out = compiler.Output(n_numpar, nampar_map, bindings)
            qt = sqlite3_quote_name(phrase.name)
            temp = "TEMP " if phrase.temp else ""
            ifnotexists = "IF NOT EXISTS " if phrase.ifnotexists else ""
            out.write("CREATE %sTABLE %s%s AS " % (temp, ifnotexists, qt))
            compiler.compile_query(bdb, phrase.query, out)
            winders, unwinders = out.getwindings()
            with compiler.bayesdb_wind(bdb, winders, unwinders):
                bdb.sql_execute(out.getvalue(), out.getbindings())
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabSim):
        assert isinstance(phrase.simulation, ast.Simulate)
        with bdb.savepoint():
            if core.bayesdb_has_generator(bdb, phrase.name):
                raise BQLError(bdb, "Name already defined as generator: %s" % (repr(phrase.name),))
            if core.bayesdb_has_table(bdb, phrase.name):
                raise BQLError(bdb, "Name already defined as table: %s" % (repr(phrase.name),))
            if not core.bayesdb_has_generator_default(bdb, phrase.simulation.generator):
                raise BQLError(bdb, "No such generator: %s" % (phrase.simulation.generator,))
            generator_id = core.bayesdb_get_generator_default(bdb, phrase.simulation.generator)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            table = core.bayesdb_generator_table(bdb, generator_id)
            qn = sqlite3_quote_name(phrase.name)
            qt = sqlite3_quote_name(table)
            qgn = sqlite3_quote_name(phrase.simulation.generator)
            column_names = phrase.simulation.columns
            qcns = map(sqlite3_quote_name, column_names)
            cursor = bdb.sql_execute("PRAGMA table_info(%s)" % (qt,))
            column_sqltypes = {}
            for _colno, name, sqltype, _nonnull, _default, _primary in cursor:
                assert casefold(name) not in column_sqltypes
                column_sqltypes[casefold(name)] = sqltype
            assert 0 < len(column_sqltypes)
            for column_name in column_names:
                if casefold(column_name) not in column_sqltypes:
                    raise BQLError(
                        bdb,
                        "No such column"
                        " in generator %s table %s: %s"
                        % (repr(phrase.simulation.generator), repr(table), repr(column_name)),
                    )
            for column_name, _expression in phrase.simulation.constraints:
                if casefold(column_name) not in column_sqltypes:
                    raise BQLError(
                        bdb,
                        "No such column"
                        " in generator %s table %s: %s"
                        % (repr(phrase.simulation.generator), repr(table), repr(column_name)),
                    )
            # XXX Move to compiler.py.
            # XXX Copypasta of this in compile_simulate!
            out = compiler.Output(n_numpar, nampar_map, bindings)
            out.write("SELECT ")
            with compiler.compiling_paren(bdb, out, "CAST(", " AS INTEGER)"):
                compiler.compile_nobql_expression(bdb, phrase.simulation.nsamples, out)
            out.write(", ")
            with compiler.compiling_paren(bdb, out, "CAST(", " AS INTEGER)"):
                compiler.compile_nobql_expression(bdb, phrase.simulation.modelno, out)
            for _column_name, expression in phrase.simulation.constraints:
                out.write(", ")
                compiler.compile_nobql_expression(bdb, expression, out)
            winders, unwinders = out.getwindings()
            with compiler.bayesdb_wind(bdb, winders, unwinders):
                cursor = bdb.sql_execute(out.getvalue(), out.getbindings()).fetchall()
            assert len(cursor) == 1
            nsamples = cursor[0][0]
            assert isinstance(nsamples, int)
            modelno = cursor[0][1]
            assert modelno is None or isinstance(modelno, int)
            constraints = [
                (core.bayesdb_generator_column_number(bdb, generator_id, name), value)
                for (name, _expression), value in zip(phrase.simulation.constraints, cursor[0][2:])
            ]
            colnos = [core.bayesdb_generator_column_number(bdb, generator_id, name) for name in column_names]
            bdb.sql_execute(
                "CREATE %sTABLE %s%s (%s)"
                % (
                    "TEMP " if phrase.temp else "",
                    "IF NOT EXISTS " if phrase.ifnotexists else "",
                    qn,
                    ",".join(
                        "%s %s" % (qcn, column_sqltypes[casefold(column_name)])
                        for qcn, column_name in zip(qcns, column_names)
                    ),
                )
            )
            insert_sql = """
                INSERT INTO %s (%s) VALUES (%s)
            """ % (
                qn,
                ",".join(qcns),
                ",".join("?" for qcn in qcns),
            )
            for row in bqlfn.bayesdb_simulate(
                bdb, generator_id, constraints, colnos, modelno=modelno, numpredictions=nsamples
            ):
                bdb.sql_execute(insert_sql, row)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropTab):
        with bdb.savepoint():
            sql = "SELECT COUNT(*) FROM bayesdb_generator WHERE tabname = ?"
            cursor = bdb.sql_execute(sql, (phrase.name,))
            if 0 < cursor_value(cursor):
                # XXX Automatically delete the generators?  Generators
                # are more interesting than triggers and indices, so
                # automatic deletion is not obviously right.
                raise BQLError(bdb, "Table still in use by generators: %s" % (repr(phrase.name),))
            bdb.sql_execute("DELETE FROM bayesdb_column WHERE tabname = ?", (phrase.name,))
            ifexists = "IF EXISTS " if phrase.ifexists else ""
            qt = sqlite3_quote_name(phrase.name)
            return bdb.sql_execute("DROP TABLE %s%s" % (ifexists, qt))

    if isinstance(phrase, ast.AlterTab):
        with bdb.savepoint():
            table = phrase.table
            if not core.bayesdb_has_table(bdb, table):
                raise BQLError(bdb, "No such table: %s" % (repr(table),))
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterTabRenameTab):
                    # If the names differ only in case, we have to do
                    # some extra work because SQLite will reject the
                    # table rename.  Note that we may even have table
                    # == cmd.name here, but if the stored table name
                    # differs in case from cmd.name, we want to update
                    # it anyway.
                    if casefold(table) == casefold(cmd.name):
                        # Go via a temporary table.
                        temp = table + "_temp"
                        while core.bayesdb_has_table(bdb, temp) or core.bayesdb_has_generator(bdb, temp):
                            temp += "_temp"
                        rename_table(bdb, table, temp)
                        rename_table(bdb, temp, cmd.name)
                    else:
                        # Make sure nothing else has this name and
                        # rename it.
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(bdb, "Name already defined as table" ": %s" % (repr(cmd.name),))
                        if core.bayesdb_has_generator(bdb, cmd.name):
                            raise BQLError(bdb, "Name already defined" " as generator: %s" % (repr(cmd.name),))
                        rename_table(bdb, table, cmd.name)
                    # Remember the new name for subsequent commands.
                    table = cmd.name
                elif isinstance(cmd, ast.AlterTabRenameCol):
                    # XXX Need to deal with this in the compiler.
                    raise NotImplementedError("Renaming columns" " not yet implemented.")
                    # Make sure the old name exist and the new name does not.
                    old_folded = casefold(cmd.old)
                    new_folded = casefold(cmd.new)
                    if old_folded != new_folded:
                        if not core.bayesdb_table_has_column(bdb, table, cmd.old):
                            raise BQLError(bdb, "No such column in table %s" ": %s" % (repr(table), repr(cmd.old)))
                        if core.bayesdb_table_has_column(bdb, table, cmd.new):
                            raise BQLError(
                                bdb, "Column already exists" " in table %s: %s" % (repr(table), repr(cmd.new))
                            )
                    # Update bayesdb_column.  Everything else refers
                    # to columns by (tabname, colno) pairs rather than
                    # by names.
                    update_column_sql = """
                        UPDATE bayesdb_column SET name = :new
                            WHERE tabname = :table AND name = :old
                    """
                    total_changes = bdb.sqlite3.total_changes
                    bdb.sql_execute(update_column_sql, {"table": table, "old": cmd.old, "new": cmd.new})
                    assert bdb.sqlite3.total_changes - total_changes == 1
                    # ...except metamodels may have the (case-folded)
                    # name cached.
                    if old_folded != new_folded:
                        generators_sql = """
                            SELECT id FROM bayesdb_generator WHERE tabname = ?
                        """
                        cursor = bdb.sql_execute(generators_sql, (table,))
                        for (generator_id,) in cursor:
                            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
                            metamodel.rename_column(bdb, generator_id, old_folded, new_folded)
                elif isinstance(cmd, ast.AlterTabSetDefGen):
                    if not core.bayesdb_has_generator(bdb, cmd.generator):
                        raise BQLError(bdb, "No such generator: %s" % (repr(cmd.generator),))
                    generator_id = core.bayesdb_get_generator(bdb, cmd.generator)
                    unset_default_sql = """
                        UPDATE bayesdb_generator SET defaultp = 0
                            WHERE tabname = ? AND defaultp
                    """
                    total_changes = bdb.sqlite3.total_changes
                    bdb.sql_execute(unset_default_sql, (table,))
                    assert bdb.sqlite3.total_changes - total_changes in (0, 1)
                    set_default_sql = """
                        UPDATE bayesdb_generator SET defaultp = 1 WHERE id = ?
                    """
                    total_changes = bdb.sqlite3.total_changes
                    bdb.sql_execute(set_default_sql, (generator_id,))
                    assert bdb.sqlite3.total_changes - total_changes == 1
                elif isinstance(cmd, ast.AlterTabUnsetDefGen):
                    unset_default_sql = """
                        UPDATE bayesdb_generator SET defaultp = 0
                            WHERE tabname = ? AND defaultp
                    """
                    total_changes = bdb.sqlite3.total_changes
                    bdb.sql_execute(unset_default_sql, (table,))
                    assert bdb.sqlite3.total_changes - total_changes in (0, 1)
                else:
                    assert False, "Invalid alter table command: %s" % (cmd,)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateGen):
        # Find the metamodel.
        if phrase.metamodel not in bdb.metamodels:
            raise BQLError(bdb, "No such metamodel: %s" % (repr(phrase.metamodel),))
        metamodel = bdb.metamodels[phrase.metamodel]

        # Let the metamodel parse the schema itself and call
        # create_generator with the modelled columns.
        with bdb.savepoint():

            def instantiate(columns):
                return instantiate_generator(
                    bdb,
                    phrase.name,
                    phrase.table,
                    metamodel,
                    columns,
                    ifnotexists=phrase.ifnotexists,
                    default=phrase.default,
                )

            metamodel.create_generator(bdb, phrase.table, phrase.schema, instantiate)

        # All done.  Nothing to return.
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropGen):
        with bdb.savepoint():
            if not core.bayesdb_has_generator(bdb, phrase.name):
                if phrase.ifexists:
                    return empty_cursor(bdb)
                raise BQLError(bdb, "No such generator: %s" % (repr(phrase.name),))
            generator_id = core.bayesdb_get_generator(bdb, phrase.name)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)

            # Metamodel-specific destruction.
            metamodel.drop_generator(bdb, generator_id)

            # Drop the columns, models, and, finally, generator.
            drop_columns_sql = """
                DELETE FROM bayesdb_generator_column WHERE generator_id = ?
            """
            bdb.sql_execute(drop_columns_sql, (generator_id,))
            drop_model_sql = """
                DELETE FROM bayesdb_generator_model WHERE generator_id = ?
            """
            bdb.sql_execute(drop_model_sql, (generator_id,))
            drop_generator_sql = """
                DELETE FROM bayesdb_generator WHERE id = ?
            """
            bdb.sql_execute(drop_generator_sql, (generator_id,))
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AlterGen):
        with bdb.savepoint():
            generator = phrase.generator
            if not core.bayesdb_has_generator(bdb, generator):
                raise BQLError(bdb, "No such generator: %s" % (repr(generator),))
            generator_id = core.bayesdb_get_generator(bdb, generator)
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterGenRenameGen):
                    # Make sure nothing else has this name.
                    if casefold(generator) != casefold(cmd.name):
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(bdb, "Name already defined as table" ": %s" % (repr(cmd.name),))
                        if core.bayesdb_has_generator(bdb, cmd.name):
                            raise BQLError(bdb, "Name already defined" " as generator: %s" % (repr(cmd.name),))
                    # Update bayesdb_generator.  Everything else
                    # refers to it by id.
                    update_generator_sql = """
                        UPDATE bayesdb_generator SET name = ? WHERE id = ?
                    """
                    total_changes = bdb.sqlite3.total_changes
                    bdb.sql_execute(update_generator_sql, (cmd.name, generator_id))
                    assert bdb.sqlite3.total_changes - total_changes == 1
                    # Remember the new name for subsequent commands.
                    generator = cmd.name
                else:
                    assert False, "Invalid ALTER GENERATOR command: %s" % (repr(cmd),)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.InitModels):
        if not core.bayesdb_has_generator_default(bdb, phrase.generator):
            raise BQLError(bdb, "No such generator: %s" % (phrase.generator,))
        generator_id = core.bayesdb_get_generator_default(bdb, phrase.generator)
        modelnos = range(phrase.nmodels)
        model_config = None  # XXX For now.

        with bdb.savepoint():
            # Find the model numbers.  Omit existing ones for
            # ifnotexists; reject existing ones otherwise.
            if phrase.ifnotexists:
                modelnos = set(
                    modelno for modelno in modelnos if not core.bayesdb_generator_has_model(bdb, generator_id, modelno)
                )
            else:
                existing = set(
                    modelno for modelno in modelnos if core.bayesdb_generator_has_model(bdb, generator_id, modelno)
                )
                if 0 < len(existing):
                    raise BQLError(
                        bdb, "Generator %s already has models: %s" % (repr(phrase.generator), sorted(existing))
                    )

            # Stop now if there's nothing to initialize.
            if len(modelnos) == 0:
                return

            # Create the bayesdb_generator_model records.
            modelnos = sorted(modelnos)
            insert_model_sql = """
                INSERT INTO bayesdb_generator_model
                    (generator_id, modelno, iterations)
                    VALUES (:generator_id, :modelno, :iterations)
            """
            for modelno in modelnos:
                bdb.sql_execute(insert_model_sql, {"generator_id": generator_id, "modelno": modelno, "iterations": 0})

            # Do metamodel-specific initialization.
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            metamodel.initialize_models(bdb, generator_id, modelnos, model_config)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AnalyzeModels):
        if not phrase.wait:
            raise NotImplementedError("No background analysis -- use WAIT.")
        # WARNING: It is the metamodel's responsibility to work in a
        # transaction.
        #
        # WARNING: It is the metamodel's responsibility to update the
        # iteration count in bayesdb_generator_model records.
        #
        # We do this so that the metamodel can save incremental
        # progress in case of ^C in the middle.
        #
        # XXX Put these warning somewhere more appropriate.
        if not core.bayesdb_has_generator_default(bdb, phrase.generator):
            raise BQLError(bdb, "No such generator: %s" % (phrase.generator,))
        generator_id = core.bayesdb_get_generator_default(bdb, phrase.generator)
        metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
        # XXX Should allow parameters for iterations and ckpt/iter.
        metamodel.analyze_models(
            bdb,
            generator_id,
            modelnos=phrase.modelnos,
            iterations=phrase.iterations,
            max_seconds=phrase.seconds,
            ckpt_iterations=phrase.ckpt_iterations,
            ckpt_seconds=phrase.ckpt_seconds,
        )
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropModels):
        with bdb.savepoint():
            generator_id = core.bayesdb_get_generator_default(bdb, phrase.generator)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            modelnos = None
            if phrase.modelnos is not None:
                lookup_model_sql = """
                    SELECT COUNT(*) FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                """
                modelnos = sorted(list(phrase.modelnos))
                for modelno in modelnos:
                    cursor = bdb.sql_execute(lookup_model_sql, {"generator_id": generator_id, "modelno": modelno})
                    if cursor_value(cursor) == 0:
                        raise BQLError(
                            bdb, "No such model" " in generator %s: %s" % (repr(phrase.generator), repr(modelno))
                        )
            metamodel.drop_models(bdb, generator_id, modelnos=modelnos)
            if modelnos is None:
                drop_models_sql = """
                    DELETE FROM bayesdb_generator_model WHERE generator_id = ?
                """
                bdb.sql_execute(drop_models_sql, (generator_id,))
            else:
                drop_model_sql = """
                    DELETE FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                """
                for modelno in modelnos:
                    bdb.sql_execute(drop_model_sql, {"generator_id": generator_id, "modelno": modelno})
        return empty_cursor(bdb)

    assert False  # XXX
Example #29
0
def execute_phrase(bdb, phrase, bindings=()):
    """Execute the BQL AST phrase `phrase` and return a cursor of results."""
    if isinstance(phrase, ast.Parametrized):
        n_numpar = phrase.n_numpar
        nampar_map = phrase.nampar_map
        phrase = phrase.phrase
        assert 0 < n_numpar
    else:
        n_numpar = 0
        nampar_map = None
        # Ignore extraneous bindings.  XXX Bad idea?

    if ast.is_query(phrase):
        # Compile the query in the transaction in case we need to
        # execute subqueries to determine column lists.  Compiling is
        # a quick tree descent, so this should be fast.
        out = compiler.Output(n_numpar, nampar_map, bindings)
        with bdb.savepoint():
            compiler.compile_query(bdb, phrase, out)
        winders, unwinders = out.getwindings()
        return execute_wound(bdb, winders, unwinders, out.getvalue(),
                             out.getbindings())

    if isinstance(phrase, ast.Begin):
        txn.bayesdb_begin_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Rollback):
        txn.bayesdb_rollback_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Commit):
        txn.bayesdb_commit_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabAs):
        assert ast.is_query(phrase.query)
        with bdb.savepoint():
            if core.bayesdb_has_table(bdb, phrase.name):
                if phrase.ifnotexists:
                    return empty_cursor(bdb)
                else:
                    raise BQLError(
                        bdb, 'Name already defined as table: %s' %
                        (repr(phrase.name), ))
            out = compiler.Output(n_numpar, nampar_map, bindings)
            qt = sqlite3_quote_name(phrase.name)
            temp = 'TEMP ' if phrase.temp else ''
            ifnotexists = 'IF NOT EXISTS ' if phrase.ifnotexists else ''
            out.write('CREATE %sTABLE %s%s AS ' % (temp, ifnotexists, qt))
            compiler.compile_query(bdb, phrase.query, out)
            winders, unwinders = out.getwindings()
            with compiler.bayesdb_wind(bdb, winders, unwinders):
                bdb.sql_execute(out.getvalue(), out.getbindings())
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabCsv):
        with bdb.savepoint():
            table_exists = core.bayesdb_has_table(bdb, phrase.name)
            if table_exists:
                if phrase.ifnotexists:
                    return empty_cursor(bdb)
                else:
                    raise BQLError(
                        bdb,
                        'Table already exists: %s' % (repr(phrase.name), ))
            bayesdb_read_csv_file(bdb,
                                  phrase.name,
                                  phrase.csv,
                                  header=True,
                                  create=True)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropTab):
        with bdb.savepoint():
            sql = 'SELECT COUNT(*) FROM bayesdb_population WHERE tabname = ?'
            cursor = bdb.sql_execute(sql, (phrase.name, ))
            if 0 < cursor_value(cursor):
                raise BQLError(
                    bdb, 'Table still in use by populations: %s' %
                    (repr(phrase.name), ))
            bdb.sql_execute('DELETE FROM bayesdb_column WHERE tabname = ?',
                            (phrase.name, ))
            ifexists = 'IF EXISTS ' if phrase.ifexists else ''
            qt = sqlite3_quote_name(phrase.name)
            return bdb.sql_execute('DROP TABLE %s%s' % (ifexists, qt))

    if isinstance(phrase, ast.AlterTab):
        with bdb.savepoint():
            table = phrase.table
            if not core.bayesdb_has_table(bdb, table):
                raise BQLError(bdb, 'No such table: %s' % (repr(table), ))
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterTabRenameTab):
                    # If the names differ only in case, we have to do
                    # some extra work because SQLite will reject the
                    # table rename.  Note that we may even have table
                    # == cmd.name here, but if the stored table name
                    # differs in case from cmd.name, we want to update
                    # it anyway.
                    if casefold(table) == casefold(cmd.name):
                        # Go via a temporary table.
                        temp = table + '_temp'
                        while core.bayesdb_has_table(bdb, temp):
                            temp += '_temp'
                        rename_table(bdb, table, temp)
                        rename_table(bdb, temp, cmd.name)
                    else:
                        # Make sure nothing else has this name and
                        # rename it.
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined as table'
                                ': %s' % (repr(cmd.name), ))
                        rename_table(bdb, table, cmd.name)
                    # Remember the new name for subsequent commands.
                    table = cmd.name
                elif isinstance(cmd, ast.AlterTabRenameCol):
                    # XXX Need to deal with this in the compiler.
                    raise NotImplementedError('Renaming columns'
                                              ' not yet implemented.')
                    # Make sure the old name exist and the new name does not.
                    old_folded = casefold(cmd.old)
                    new_folded = casefold(cmd.new)
                    if old_folded != new_folded:
                        if not core.bayesdb_table_has_column(
                                bdb, table, cmd.old):
                            raise BQLError(
                                bdb, 'No such column in table %s'
                                ': %s' % (repr(table), repr(cmd.old)))
                        if core.bayesdb_table_has_column(bdb, table, cmd.new):
                            raise BQLError(
                                bdb, 'Column already exists'
                                ' in table %s: %s' %
                                (repr(table), repr(cmd.new)))
                    # Update bayesdb_column.  Everything else refers
                    # to columns by (tabname, colno) pairs rather than
                    # by names.
                    update_column_sql = '''
                        UPDATE bayesdb_column SET name = :new
                            WHERE tabname = :table AND name = :old
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(update_column_sql, {
                        'table': table,
                        'old': cmd.old,
                        'new': cmd.new,
                    })
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                    # ...except metamodels may have the (case-folded)
                    # name cached.
                    if old_folded != new_folded:
                        generators_sql = '''
                            SELECT id FROM bayesdb_generator WHERE tabname = ?
                        '''
                        cursor = bdb.sql_execute(generators_sql, (table, ))
                        for (generator_id, ) in cursor:
                            metamodel = core.bayesdb_generator_metamodel(
                                bdb, generator_id)
                            metamodel.rename_column(bdb, generator_id,
                                                    old_folded, new_folded)
                else:
                    assert False, 'Invalid alter table command: %s' % \
                        (cmd,)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.GuessSchema):
        if not core.bayesdb_has_table(bdb, phrase.table):
            raise BQLError(bdb, 'No such table : %s' % phrase.table)
        out = compiler.Output(0, {}, {})
        with bdb.savepoint():
            qt = sqlite3_quote_name(phrase.table)
            temptable = bdb.temp_table_name()
            qtt = sqlite3_quote_name(temptable)
            cursor = bdb.sql_execute('SELECT * FROM %s' % (qt, ))
            column_names = [d[0] for d in cursor.description]
            rows = cursor.fetchall()
            stattypes = bayesdb_guess_stattypes(column_names, rows)
            distinct_value_counts = [
                len(set([row[i] for row in rows]))
                for i in range(len(column_names))
            ]
            out.winder(
                '''
                CREATE TEMP TABLE %s (column TEXT, stattype TEXT, num_distinct INTEGER, reason TEXT)
            ''' % (qtt), ())
            for cn, st, ct in zip(column_names, stattypes,
                                  distinct_value_counts):
                out.winder(
                    '''
                    INSERT INTO %s VALUES (?, ?, ?, ?)
                ''' % (qtt), (cn, st[0], ct, st[1]))
            out.write('SELECT * FROM %s' % (qtt, ))
            out.unwinder('DROP TABLE %s' % (qtt, ), ())
        winders, unwinders = out.getwindings()
        return execute_wound(bdb, winders, unwinders, out.getvalue(),
                             out.getbindings())

    if isinstance(phrase, ast.CreatePop):
        with bdb.savepoint():
            _create_population(bdb, phrase)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropPop):
        with bdb.savepoint():
            if not core.bayesdb_has_population(bdb, phrase.name):
                if phrase.ifexists:
                    return empty_cursor(bdb)
                raise BQLError(bdb, 'No such population: %r' % (phrase.name, ))
            population_id = core.bayesdb_get_population(bdb, phrase.name)
            generator_ids = core.bayesdb_population_generators(
                bdb, population_id)
            if generator_ids:
                generators = [
                    core.bayesdb_generator_name(bdb, gid)
                    for gid in generator_ids
                ]
                raise BQLError(
                    bdb, 'Population %r still has metamodels: %r' %
                    (phrase.name, generators))
            # XXX helpful error checking if generators still exist
            # XXX check change counts
            bdb.sql_execute(
                '''
                DELETE FROM bayesdb_variable WHERE population_id = ?
            ''', (population_id, ))
            bdb.sql_execute(
                '''
                DELETE FROM bayesdb_population WHERE id = ?
            ''', (population_id, ))
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AlterPop):
        with bdb.savepoint():
            population = phrase.population
            if not core.bayesdb_has_population(bdb, population):
                raise BQLError(bdb,
                               'No such population: %s' % (repr(population), ))
            population_id = core.bayesdb_get_population(bdb, population)
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterPopAddVar):
                    # Ensure column exists in base table.
                    table = core.bayesdb_population_table(bdb, population_id)
                    if not core.bayesdb_table_has_column(bdb, table, cmd.name):
                        raise BQLError(
                            bdb,
                            'No such variable in base table: %s' % (cmd.name))
                    # Ensure variable not already in population.
                    if core.bayesdb_has_variable(bdb, population_id, None,
                                                 cmd.name):
                        raise BQLError(
                            bdb,
                            'Variable already in population: %s' % (cmd.name))
                    # Ensure there is at least observation in the column.
                    qt = sqlite3_quote_name(table)
                    qc = sqlite3_quote_name(cmd.name)
                    cursor = bdb.sql_execute(
                        'SELECT COUNT(*) FROM %s WHERE %s IS NOT NULL' %
                        (qt, qc))
                    if cursor_value(cursor) == 0:
                        raise BQLError(
                            bdb, 'Cannot add variable without any values: %s' %
                            (cmd.name))
                    # If stattype is None, guess.
                    if cmd.stattype is None:
                        cursor = bdb.sql_execute('SELECT %s FROM %s' %
                                                 (qc, qt))
                        rows = cursor.fetchall()
                        [stattype,
                         reason] = bayesdb_guess_stattypes([cmd.name], rows)[0]
                        # Fail if trying to model a key.
                        if stattype == 'key':
                            raise BQLError(
                                bdb, 'Values in column %s appear to be keys.' %
                                (cmd.name, ))
                        # Fail if cannot determine a stattype.
                        elif stattype == 'ignore':
                            raise BQLError(
                                bdb, 'Failed to determine a stattype for %s, '
                                'please specify one manually.' % (cmd.name, ))
                    # If user specified stattype, ensure it exists.
                    elif not core.bayesdb_has_stattype(bdb, cmd.stattype):
                        raise BQLError(bdb,
                                       'Invalid stattype: %s' % (cmd.stattype))
                    else:
                        stattype = cmd.stattype
                    # Check that strings are not being modeled as numerical.
                    if stattype == 'numerical' \
                            and _column_contains_string(bdb, table, cmd.name):
                        raise BQLError(
                            bdb,
                            'Numerical column contains string values: %r ' %
                            (qc, ))
                    with bdb.savepoint():
                        # Add the variable to the population.
                        core.bayesdb_add_variable(bdb, population_id, cmd.name,
                                                  stattype)
                        colno = core.bayesdb_variable_number(
                            bdb, population_id, None, cmd.name)
                        # Add the variable to each (initialized) metamodel in
                        # the population.
                        generator_ids = filter(
                            lambda g: core.bayesdb_generator_modelnos(bdb, g),
                            core.bayesdb_population_generators(
                                bdb, population_id),
                        )
                        for generator_id in generator_ids:
                            # XXX Omit needless bayesdb_generator_column table
                            # Github issue #441.
                            bdb.sql_execute(
                                '''
                                INSERT INTO bayesdb_generator_column
                                    VALUES (:generator_id, :colno, :stattype)
                            ''', {
                                    'generator_id': generator_id,
                                    'colno': colno,
                                    'stattype': stattype,
                                })
                            metamodel = core.bayesdb_generator_metamodel(
                                bdb, generator_id)
                            metamodel.add_column(bdb, generator_id, colno)
                elif isinstance(cmd, ast.AlterPopStatType):
                    # Check the no metamodels are defined for this population.
                    generators = core.bayesdb_population_generators(
                        bdb, population_id)
                    if generators:
                        raise BQLError(
                            bdb,
                            'Cannot update statistical types for population '
                            '%s, it has metamodels: %s' % (
                                repr(population),
                                repr(generators),
                            ))
                    # Check all the variables are in the population.
                    unknown = [
                        c for c in cmd.names if not core.bayesdb_has_variable(
                            bdb, population_id, None, c)
                    ]
                    if unknown:
                        raise BQLError(
                            bdb, 'No such variables in population: %s' %
                            (repr(unknown)))
                    # Check the statistical type is valid.
                    if not core.bayesdb_has_stattype(bdb, cmd.stattype):
                        raise BQLError(
                            bdb, 'Invalid statistical type: %r' %
                            (repr(cmd.stattype), ))
                    # Check that strings are not being modeled as numerical.
                    if cmd.stattype == 'numerical':
                        table = core.bayesdb_population_table(
                            bdb, population_id)
                        numerical_string_vars = [
                            col for col in cmd.names
                            if _column_contains_string(bdb, table, col)
                        ]
                        if numerical_string_vars:
                            raise BQLError(
                                bdb, 'Columns with string values modeled as '
                                'numerical: %r' % (numerical_string_vars, ))
                    # Perform the stattype update.
                    colnos = [
                        core.bayesdb_variable_number(bdb, population_id, None,
                                                     c) for c in cmd.names
                    ]
                    qcolnos = ','.join('%d' % (colno, ) for colno in colnos)
                    update_stattype_sql = '''
                        UPDATE bayesdb_variable SET stattype = ?
                            WHERE population_id = ? AND colno IN (%s)
                    ''' % (qcolnos, )
                    bdb.sql_execute(update_stattype_sql, (
                        casefold(cmd.stattype),
                        population_id,
                    ))
                else:
                    assert False, 'Invalid ALTER POPULATION command: %s' % \
                        (repr(cmd),)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateGen):
        # Find the population.
        if not core.bayesdb_has_population(bdb, phrase.population):
            raise BQLError(bdb,
                           'No such population: %r' % (phrase.population, ))
        population_id = core.bayesdb_get_population(bdb, phrase.population)
        table = core.bayesdb_population_table(bdb, population_id)

        # Find the metamodel, or use the default.
        metamodel_name = phrase.metamodel
        if phrase.metamodel is None:
            metamodel_name = 'cgpm'
        if metamodel_name not in bdb.metamodels:
            raise BQLError(bdb,
                           'No such metamodel: %s' % (repr(metamodel_name), ))
        metamodel = bdb.metamodels[metamodel_name]

        with bdb.savepoint():
            if core.bayesdb_has_generator(bdb, population_id, phrase.name):
                if not phrase.ifnotexists:
                    raise BQLError(
                        bdb, 'Name already defined as generator: %s' %
                        (repr(phrase.name), ))
            else:
                # Insert a record into bayesdb_generator and get the
                # assigned id.
                bdb.sql_execute(
                    '''
                    INSERT INTO bayesdb_generator
                        (name, tabname, population_id, metamodel)
                        VALUES (?, ?, ?, ?)
                ''', (phrase.name, table, population_id, metamodel.name()))
                generator_id = core.bayesdb_get_generator(
                    bdb, population_id, phrase.name)

                # Populate bayesdb_generator_column.
                #
                # XXX Omit needless bayesdb_generator_column table --
                # Github issue #441.
                bdb.sql_execute(
                    '''
                    INSERT INTO bayesdb_generator_column
                        (generator_id, colno, stattype)
                        SELECT :generator_id, colno, stattype
                            FROM bayesdb_variable
                            WHERE population_id = :population_id
                                AND generator_id IS NULL
                ''', {
                        'generator_id': generator_id,
                        'population_id': population_id,
                    })

                # Do any metamodel-specific initialization.
                metamodel.create_generator(bdb,
                                           generator_id,
                                           phrase.schema,
                                           baseline=phrase.baseline)

                # Populate bayesdb_generator_column with any latent
                # variables that metamodel.create_generator has added
                # with bayesdb_add_latent.
                bdb.sql_execute(
                    '''
                    INSERT INTO bayesdb_generator_column
                        (generator_id, colno, stattype)
                        SELECT :generator_id, colno, stattype
                            FROM bayesdb_variable
                            WHERE population_id = :population_id
                                AND generator_id = :generator_id
                ''', {
                        'generator_id': generator_id,
                        'population_id': population_id,
                    })

        # All done.  Nothing to return.
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropGen):
        with bdb.savepoint():
            if not core.bayesdb_has_generator(bdb, None, phrase.name):
                if phrase.ifexists:
                    return empty_cursor(bdb)
                raise BQLError(bdb,
                               'No such generator: %s' % (repr(phrase.name), ))
            generator_id = core.bayesdb_get_generator(bdb, None, phrase.name)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)

            # Metamodel-specific destruction.
            metamodel.drop_generator(bdb, generator_id)

            # Drop the columns, models, and, finally, generator.
            drop_columns_sql = '''
                DELETE FROM bayesdb_generator_column WHERE generator_id = ?
            '''
            bdb.sql_execute(drop_columns_sql, (generator_id, ))
            drop_model_sql = '''
                DELETE FROM bayesdb_generator_model WHERE generator_id = ?
            '''
            bdb.sql_execute(drop_model_sql, (generator_id, ))
            drop_generator_sql = '''
                DELETE FROM bayesdb_generator WHERE id = ?
            '''
            bdb.sql_execute(drop_generator_sql, (generator_id, ))
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AlterGen):
        with bdb.savepoint():
            generator = phrase.generator
            if not core.bayesdb_has_generator(bdb, None, generator):
                raise BQLError(bdb,
                               'No such generator: %s' % (repr(generator), ))
            generator_id = core.bayesdb_get_generator(bdb, None, generator)
            cmds_generic = []
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterGenRenameGen):
                    # Disable modelnos with AlterGenRenameGen.
                    if phrase.modelnos is not None:
                        raise BQLError(bdb, 'Cannot specify models for RENAME')
                    # Make sure nothing else has this name.
                    if casefold(generator) != casefold(cmd.name):
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined as table'
                                ': %s' % (repr(cmd.name), ))
                        if core.bayesdb_has_generator(bdb, None, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined'
                                ' as generator: %s' % (repr(cmd.name), ))
                    # Update bayesdb_generator.  Everything else
                    # refers to it by id.
                    update_generator_sql = '''
                        UPDATE bayesdb_generator SET name = ? WHERE id = ?
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(update_generator_sql,
                                    (cmd.name, generator_id))
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                    # Remember the new name for subsequent commands.
                    generator = cmd.name
                elif isinstance(cmd, ast.AlterGenGeneric):
                    cmds_generic.append(cmd.command)
                else:
                    assert False, 'Invalid ALTER GENERATOR command: %s' % \
                        (repr(cmd),)
            if cmds_generic:
                modelnos = phrase.modelnos
                modelnos_invalid = None if modelnos is None else [
                    modelno for modelno in modelnos
                    if not core.bayesdb_generator_has_model(
                        bdb, generator_id, modelno)
                ]
                if modelnos_invalid:
                    raise BQLError(
                        bdb, 'No such models in generator %s: %s' %
                        (repr(phrase.generator), repr(modelnos)))
                # Call generic alternations on the metamodel.
                metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
                metamodel.alter(bdb, generator_id, modelnos, cmds_generic)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.InitModels):
        if not core.bayesdb_has_generator(bdb, None, phrase.generator):
            raise BQLError(bdb, 'No such generator: %s' % (phrase.generator, ))
        generator_id = core.bayesdb_get_generator(bdb, None, phrase.generator)
        modelnos = range(phrase.nmodels)

        with bdb.savepoint():
            # Find the model numbers.  Omit existing ones for
            # ifnotexists; reject existing ones otherwise.
            if phrase.ifnotexists:
                modelnos = set(modelno for modelno in modelnos
                               if not core.bayesdb_generator_has_model(
                                   bdb, generator_id, modelno))
            else:
                existing = set(modelno for modelno in modelnos
                               if core.bayesdb_generator_has_model(
                                   bdb, generator_id, modelno))
                if 0 < len(existing):
                    raise BQLError(
                        bdb, 'Generator %s already has models: %s' %
                        (repr(phrase.generator), sorted(existing)))

            # Stop now if there's nothing to initialize.
            if len(modelnos) == 0:
                return

            # Create the bayesdb_generator_model records.
            modelnos = sorted(modelnos)
            insert_model_sql = '''
                INSERT INTO bayesdb_generator_model
                    (generator_id, modelno, iterations)
                    VALUES (:generator_id, :modelno, :iterations)
            '''
            for modelno in modelnos:
                bdb.sql_execute(
                    insert_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                        'iterations': 0,
                    })

            # Do metamodel-specific initialization.
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            metamodel.initialize_models(bdb, generator_id, modelnos)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AnalyzeModels):
        if not phrase.wait:
            raise NotImplementedError('No background analysis -- use WAIT.')
        # WARNING: It is the metamodel's responsibility to work in a
        # transaction.
        #
        # WARNING: It is the metamodel's responsibility to update the
        # iteration count in bayesdb_generator_model records.
        #
        # We do this so that the metamodel can save incremental
        # progress in case of ^C in the middle.
        #
        # XXX Put these warning somewhere more appropriate.
        if not core.bayesdb_has_generator(bdb, None, phrase.generator):
            raise BQLError(bdb, 'No such generator: %s' % (phrase.generator, ))
        generator_id = core.bayesdb_get_generator(bdb, None, phrase.generator)
        metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
        # XXX Should allow parameters for iterations and ckpt/iter.
        metamodel.analyze_models(bdb,
                                 generator_id,
                                 modelnos=phrase.modelnos,
                                 iterations=phrase.iterations,
                                 max_seconds=phrase.seconds,
                                 ckpt_iterations=phrase.ckpt_iterations,
                                 ckpt_seconds=phrase.ckpt_seconds,
                                 program=phrase.program)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropModels):
        with bdb.savepoint():
            generator_id = core.bayesdb_get_generator(bdb, None,
                                                      phrase.generator)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            modelnos = None
            if phrase.modelnos is not None:
                lookup_model_sql = '''
                    SELECT COUNT(*) FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                '''
                modelnos = sorted(list(phrase.modelnos))
                for modelno in modelnos:
                    cursor = bdb.sql_execute(lookup_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                    })
                    if cursor_value(cursor) == 0:
                        raise BQLError(
                            bdb, 'No such model'
                            ' in generator %s: %s' %
                            (repr(phrase.generator), repr(modelno)))
            metamodel.drop_models(bdb, generator_id, modelnos=modelnos)
            if modelnos is None:
                drop_models_sql = '''
                    DELETE FROM bayesdb_generator_model WHERE generator_id = ?
                '''
                bdb.sql_execute(drop_models_sql, (generator_id, ))
            else:
                drop_model_sql = '''
                    DELETE FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                '''
                for modelno in modelnos:
                    bdb.sql_execute(drop_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                    })
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Regress):
        # Retrieve the population.
        if not core.bayesdb_has_population(bdb, phrase.population):
            raise BQLError(bdb,
                           'No such population: %r' % (phrase.population, ))
        population_id = core.bayesdb_get_population(bdb, phrase.population)
        # Retrieve the metamodel.
        generator_id = None
        if phrase.metamodel:
            if not core.bayesdb_has_generator(bdb, population_id,
                                              phrase.metamodel):
                raise BQLError(bdb,
                               'No such metamodel: %r' % (phrase.population, ))
            generator_id = core.bayesdb_get_generator(bdb, population_id,
                                                      phrase.metamodel)
        # Retrieve the target variable.
        if not core.bayesdb_has_variable(bdb, population_id, None,
                                         phrase.target):
            raise BQLError(bdb, 'No such variable: %r' % (phrase.target, ))
        colno_target = core.bayesdb_variable_number(bdb, population_id, None,
                                                    phrase.target)
        if core.bayesdb_variable_stattype(bdb, population_id, colno_target) != \
                'numerical':
            raise BQLError(
                bdb,
                'Target variable is not numerical: %r' % (phrase.target, ))
        # Build the given variables.
        if any(isinstance(col, ast.SelColAll) for col in phrase.givens):
            # Using * is not allowed to be mixed with other variables.
            if len(phrase.givens) > 1:
                raise BQLError(bdb, 'Cannot use (*) with other givens.')
            colno_givens = core.bayesdb_variable_numbers(
                bdb, population_id, None)
        else:
            if any(isinstance(col, ast.SelColSub) for col in phrase.givens):
                # Subexpression needs special compiling.
                out = compiler.Output(n_numpar, nampar_map, bindings)
                bql_compiler = compiler.BQLCompiler_None()
                givens = compiler.expand_select_columns(
                    bdb, phrase.givens, True, bql_compiler, out)
            else:
                givens = phrase.givens
            colno_givens = [
                core.bayesdb_variable_number(bdb, population_id, None,
                                             given.expression.column)
                for given in givens
            ]
        # Build the arguments to bqlfn.bayesdb_simulate.
        colno_givens_unique = set(colno for colno in colno_givens
                                  if colno != colno_target)
        if len(colno_givens_unique) == 0:
            raise BQLError(bdb, 'No matching given columns.')
        constraints = []
        colnos = [colno_target] + list(colno_givens_unique)
        nsamp = 100 if phrase.nsamp is None else phrase.nsamp.value.value
        modelnos = None if phrase.modelnos is None else str(phrase.modelnos)
        rows = bqlfn.bayesdb_simulate(bdb,
                                      population_id,
                                      generator_id,
                                      modelnos,
                                      constraints,
                                      colnos,
                                      numpredictions=nsamp)
        # Retrieve the stattypes.
        stattypes = [
            core.bayesdb_variable_stattype(bdb, population_id, colno_given)
            for colno_given in colno_givens_unique
        ]
        # Separate the target values from the given values.
        target_values = [row[0] for row in rows]
        given_values = [row[1:] for row in rows]
        given_names = [
            core.bayesdb_variable_name(bdb, population_id, given)
            for given in colno_givens_unique
        ]
        # Compute the coefficients. The import to regress_ols is here since the
        # feature depends on pandas + sklearn, so avoid module-wide import.
        from bayeslite.regress import regress_ols
        coefficients = regress_ols(target_values, given_values, given_names,
                                   stattypes)
        # Store the results in a winder.
        temptable = bdb.temp_table_name()
        qtt = sqlite3_quote_name(temptable)
        out = compiler.Output(0, {}, {})
        out.winder(
            '''
            CREATE TEMP TABLE %s (variable TEXT, coefficient REAL);
        ''' % (qtt, ), ())
        for variable, coef in coefficients:
            out.winder(
                '''
                INSERT INTO %s VALUES (?, ?)
            ''' % (qtt), (
                    variable,
                    coef,
                ))
        out.write('SELECT * FROM %s ORDER BY variable' % (qtt, ))
        out.unwinder('DROP TABLE %s' % (qtt, ), ())
        winders, unwinders = out.getwindings()
        return execute_wound(bdb, winders, unwinders, out.getvalue(),
                             out.getbindings())

    assert False  # XXX
Example #30
0
 def generator_similarity(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     # XXX Change [colno] to colno by updating IBayesDBMetamodel.
     return metamodel.row_similarity(bdb, generator_id, None, rowid,
                                     target_rowid, [colno])
Example #31
0
 def generator_predprob(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     return metamodel.logpdf_joint(bdb, generator_id,
                                   [(rowid, colno, value)], [], None)
Example #32
0
 def generator_depprob(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     depprob_list = metamodel.column_dependence_probability(
         bdb, generator_id, modelnos, colno0, colno1)
     return stats.arithmetic_mean(depprob_list)
Example #33
0
def bayesdb_insertmany(bdb, generator_id, rows):
    """Notify a generator that rows have been inserted into its table."""
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    metamodel.insertmany(bdb, generator_id, rows)
Example #34
0
def execute_phrase(bdb, phrase, bindings=()):
    """Execute the BQL AST phrase `phrase` and return a cursor of results."""
    if isinstance(phrase, ast.Parametrized):
        n_numpar = phrase.n_numpar
        nampar_map = phrase.nampar_map
        phrase = phrase.phrase
        assert 0 < n_numpar
    else:
        n_numpar = 0
        nampar_map = None
        # Ignore extraneous bindings.  XXX Bad idea?

    if ast.is_query(phrase):
        # Compile the query in the transaction in case we need to
        # execute subqueries to determine column lists.  Compiling is
        # a quick tree descent, so this should be fast.
        out = compiler.Output(n_numpar, nampar_map, bindings)
        with bdb.savepoint():
            compiler.compile_query(bdb, phrase, out)
        winders, unwinders = out.getwindings()
        return execute_wound(bdb, winders, unwinders, out.getvalue(),
                             out.getbindings())

    if isinstance(phrase, ast.Begin):
        txn.bayesdb_begin_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Rollback):
        txn.bayesdb_rollback_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.Commit):
        txn.bayesdb_commit_transaction(bdb)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabAs):
        assert ast.is_query(phrase.query)
        with bdb.savepoint():
            out = compiler.Output(n_numpar, nampar_map, bindings)
            qt = sqlite3_quote_name(phrase.name)
            temp = 'TEMP ' if phrase.temp else ''
            ifnotexists = 'IF NOT EXISTS ' if phrase.ifnotexists else ''
            out.write('CREATE %sTABLE %s%s AS ' % (temp, ifnotexists, qt))
            compiler.compile_query(bdb, phrase.query, out)
            winders, unwinders = out.getwindings()
            with compiler.bayesdb_wind(bdb, winders, unwinders):
                bdb.sql_execute(out.getvalue(), out.getbindings())
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateTabSim):
        assert isinstance(phrase.simulation, ast.Simulate)
        with bdb.savepoint():
            if core.bayesdb_has_generator(bdb, phrase.name):
                raise BQLError(
                    bdb, 'Name already defined as generator: %s' %
                    (repr(phrase.name), ))
            if core.bayesdb_has_table(bdb, phrase.name):
                raise BQLError(
                    bdb, 'Name already defined as table: %s' %
                    (repr(phrase.name), ))
            if not core.bayesdb_has_generator_default(
                    bdb, phrase.simulation.generator):
                raise BQLError(
                    bdb,
                    'No such generator: %s' % (phrase.simulation.generator, ))
            generator_id = core.bayesdb_get_generator_default(
                bdb, phrase.simulation.generator)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            table = core.bayesdb_generator_table(bdb, generator_id)
            qn = sqlite3_quote_name(phrase.name)
            qt = sqlite3_quote_name(table)
            qgn = sqlite3_quote_name(phrase.simulation.generator)
            column_names = phrase.simulation.columns
            qcns = map(sqlite3_quote_name, column_names)
            cursor = bdb.sql_execute('PRAGMA table_info(%s)' % (qt, ))
            column_sqltypes = {}
            for _colno, name, sqltype, _nonnull, _default, _primary in cursor:
                assert casefold(name) not in column_sqltypes
                column_sqltypes[casefold(name)] = sqltype
            assert 0 < len(column_sqltypes)
            for column_name in column_names:
                if casefold(column_name) not in column_sqltypes:
                    raise BQLError(
                        bdb, 'No such column'
                        ' in generator %s table %s: %s' %
                        (repr(phrase.simulation.generator), repr(table),
                         repr(column_name)))
            for column_name, _expression in phrase.simulation.constraints:
                if casefold(column_name) not in column_sqltypes:
                    raise BQLError(
                        bdb, 'No such column'
                        ' in generator %s table %s: %s' %
                        (repr(phrase.simulation.generator), repr(table),
                         repr(column_name)))
            # XXX Move to compiler.py.
            # XXX Copypasta of this in compile_simulate!
            out = compiler.Output(n_numpar, nampar_map, bindings)
            out.write('SELECT ')
            with compiler.compiling_paren(bdb, out, 'CAST(', ' AS INTEGER)'):
                compiler.compile_nobql_expression(bdb,
                                                  phrase.simulation.nsamples,
                                                  out)
            out.write(', ')
            with compiler.compiling_paren(bdb, out, 'CAST(', ' AS INTEGER)'):
                compiler.compile_nobql_expression(bdb,
                                                  phrase.simulation.modelno,
                                                  out)
            for _column_name, expression in phrase.simulation.constraints:
                out.write(', ')
                compiler.compile_nobql_expression(bdb, expression, out)
            winders, unwinders = out.getwindings()
            with compiler.bayesdb_wind(bdb, winders, unwinders):
                cursor = bdb.sql_execute(out.getvalue(),
                                         out.getbindings()).fetchall()
            assert len(cursor) == 1
            nsamples = cursor[0][0]
            assert isinstance(nsamples, int)
            modelno = cursor[0][1]
            assert modelno is None or isinstance(modelno, int)
            constraints = \
                [(core.bayesdb_generator_column_number(bdb, generator_id, name),
                        value)
                    for (name, _expression), value in
                        zip(phrase.simulation.constraints, cursor[0][2:])]
            colnos = \
                [core.bayesdb_generator_column_number(bdb, generator_id, name)
                    for name in column_names]
            bdb.sql_execute(
                'CREATE %sTABLE %s%s (%s)' %
                ('TEMP ' if phrase.temp else '',
                 'IF NOT EXISTS ' if phrase.ifnotexists else '', qn, ','.join(
                     '%s %s' % (qcn, column_sqltypes[casefold(column_name)])
                     for qcn, column_name in zip(qcns, column_names))))
            insert_sql = '''
                INSERT INTO %s (%s) VALUES (%s)
            ''' % (qn, ','.join(qcns), ','.join('?' for qcn in qcns))
            for row in bqlfn.bayesdb_simulate(bdb,
                                              generator_id,
                                              constraints,
                                              colnos,
                                              modelno=modelno,
                                              numpredictions=nsamples):
                bdb.sql_execute(insert_sql, row)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropTab):
        with bdb.savepoint():
            sql = 'SELECT COUNT(*) FROM bayesdb_generator WHERE tabname = ?'
            cursor = bdb.sql_execute(sql, (phrase.name, ))
            if 0 < cursor_value(cursor):
                # XXX Automatically delete the generators?  Generators
                # are more interesting than triggers and indices, so
                # automatic deletion is not obviously right.
                raise BQLError(
                    bdb, 'Table still in use by generators: %s' %
                    (repr(phrase.name), ))
            bdb.sql_execute('DELETE FROM bayesdb_column WHERE tabname = ?',
                            (phrase.name, ))
            ifexists = 'IF EXISTS ' if phrase.ifexists else ''
            qt = sqlite3_quote_name(phrase.name)
            return bdb.sql_execute('DROP TABLE %s%s' % (ifexists, qt))

    if isinstance(phrase, ast.AlterTab):
        with bdb.savepoint():
            table = phrase.table
            if not core.bayesdb_has_table(bdb, table):
                raise BQLError(bdb, 'No such table: %s' % (repr(table), ))
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterTabRenameTab):
                    # If the names differ only in case, we have to do
                    # some extra work because SQLite will reject the
                    # table rename.  Note that we may even have table
                    # == cmd.name here, but if the stored table name
                    # differs in case from cmd.name, we want to update
                    # it anyway.
                    if casefold(table) == casefold(cmd.name):
                        # Go via a temporary table.
                        temp = table + '_temp'
                        while core.bayesdb_has_table(bdb, temp) or \
                              core.bayesdb_has_generator(bdb, temp):
                            temp += '_temp'
                        rename_table(bdb, table, temp)
                        rename_table(bdb, temp, cmd.name)
                    else:
                        # Make sure nothing else has this name and
                        # rename it.
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined as table'
                                ': %s' % (repr(cmd.name), ))
                        if core.bayesdb_has_generator(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined'
                                ' as generator: %s' % (repr(cmd.name), ))
                        rename_table(bdb, table, cmd.name)
                    # Remember the new name for subsequent commands.
                    table = cmd.name
                elif isinstance(cmd, ast.AlterTabRenameCol):
                    # XXX Need to deal with this in the compiler.
                    raise NotImplementedError('Renaming columns'
                                              ' not yet implemented.')
                    # Make sure the old name exist and the new name does not.
                    old_folded = casefold(cmd.old)
                    new_folded = casefold(cmd.new)
                    if old_folded != new_folded:
                        if not core.bayesdb_table_has_column(
                                bdb, table, cmd.old):
                            raise BQLError(
                                bdb, 'No such column in table %s'
                                ': %s' % (repr(table), repr(cmd.old)))
                        if core.bayesdb_table_has_column(bdb, table, cmd.new):
                            raise BQLError(
                                bdb, 'Column already exists'
                                ' in table %s: %s' %
                                (repr(table), repr(cmd.new)))
                    # Update bayesdb_column.  Everything else refers
                    # to columns by (tabname, colno) pairs rather than
                    # by names.
                    update_column_sql = '''
                        UPDATE bayesdb_column SET name = :new
                            WHERE tabname = :table AND name = :old
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(update_column_sql, {
                        'table': table,
                        'old': cmd.old,
                        'new': cmd.new,
                    })
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                    # ...except metamodels may have the (case-folded)
                    # name cached.
                    if old_folded != new_folded:
                        generators_sql = '''
                            SELECT id FROM bayesdb_generator WHERE tabname = ?
                        '''
                        cursor = bdb.sql_execute(generators_sql, (table, ))
                        for (generator_id, ) in cursor:
                            metamodel = core.bayesdb_generator_metamodel(
                                bdb, generator_id)
                            metamodel.rename_column(bdb, generator_id,
                                                    old_folded, new_folded)
                elif isinstance(cmd, ast.AlterTabSetDefGen):
                    if not core.bayesdb_has_generator(bdb, cmd.generator):
                        raise BQLError(
                            bdb,
                            'No such generator: %s' % (repr(cmd.generator), ))
                    generator_id = core.bayesdb_get_generator(
                        bdb, cmd.generator)
                    bayesdb_schema_required(bdb, 6, "generator defaults")
                    unset_default_sql = '''
                        UPDATE bayesdb_generator SET defaultp = 0
                            WHERE tabname = ? AND defaultp
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(unset_default_sql, (table, ))
                    assert bdb._sqlite3.totalchanges() - total_changes in (0,
                                                                           1)
                    set_default_sql = '''
                        UPDATE bayesdb_generator SET defaultp = 1 WHERE id = ?
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(set_default_sql, (generator_id, ))
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                elif isinstance(cmd, ast.AlterTabUnsetDefGen):
                    unset_default_sql = '''
                        UPDATE bayesdb_generator SET defaultp = 0
                            WHERE tabname = ? AND defaultp
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(unset_default_sql, (table, ))
                    assert bdb._sqlite3.totalchanges() - total_changes in (0,
                                                                           1)
                else:
                    assert False, 'Invalid alter table command: %s' % \
                        (cmd,)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.CreateGen):
        # Find the metamodel.
        if phrase.metamodel not in bdb.metamodels:
            raise BQLError(
                bdb, 'No such metamodel: %s' % (repr(phrase.metamodel), ))
        metamodel = bdb.metamodels[phrase.metamodel]

        # Let the metamodel parse the schema itself and call
        # create_generator with the modelled columns.
        with bdb.savepoint():
            if core.bayesdb_has_generator(bdb, phrase.name):
                if not phrase.ifnotexists:
                    raise BQLError(
                        bdb, 'Name already defined as generator: %s' %
                        (repr(phrase.name), ))
            else:

                def instantiate(columns):
                    return instantiate_generator(bdb,
                                                 phrase.name,
                                                 phrase.table,
                                                 metamodel,
                                                 columns,
                                                 default=phrase.default)

                metamodel.create_generator(bdb, phrase.table, phrase.schema,
                                           instantiate)

        # All done.  Nothing to return.
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropGen):
        with bdb.savepoint():
            if not core.bayesdb_has_generator(bdb, phrase.name):
                if phrase.ifexists:
                    return empty_cursor(bdb)
                raise BQLError(bdb,
                               'No such generator: %s' % (repr(phrase.name), ))
            generator_id = core.bayesdb_get_generator(bdb, phrase.name)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)

            # Metamodel-specific destruction.
            metamodel.drop_generator(bdb, generator_id)

            # Drop the columns, models, and, finally, generator.
            drop_columns_sql = '''
                DELETE FROM bayesdb_generator_column WHERE generator_id = ?
            '''
            bdb.sql_execute(drop_columns_sql, (generator_id, ))
            drop_model_sql = '''
                DELETE FROM bayesdb_generator_model WHERE generator_id = ?
            '''
            bdb.sql_execute(drop_model_sql, (generator_id, ))
            drop_generator_sql = '''
                DELETE FROM bayesdb_generator WHERE id = ?
            '''
            bdb.sql_execute(drop_generator_sql, (generator_id, ))
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AlterGen):
        with bdb.savepoint():
            generator = phrase.generator
            if not core.bayesdb_has_generator(bdb, generator):
                raise BQLError(bdb,
                               'No such generator: %s' % (repr(generator), ))
            generator_id = core.bayesdb_get_generator(bdb, generator)
            for cmd in phrase.commands:
                if isinstance(cmd, ast.AlterGenRenameGen):
                    # Make sure nothing else has this name.
                    if casefold(generator) != casefold(cmd.name):
                        if core.bayesdb_has_table(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined as table'
                                ': %s' % (repr(cmd.name), ))
                        if core.bayesdb_has_generator(bdb, cmd.name):
                            raise BQLError(
                                bdb, 'Name already defined'
                                ' as generator: %s' % (repr(cmd.name), ))
                    # Update bayesdb_generator.  Everything else
                    # refers to it by id.
                    update_generator_sql = '''
                        UPDATE bayesdb_generator SET name = ? WHERE id = ?
                    '''
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(update_generator_sql,
                                    (cmd.name, generator_id))
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                    # Remember the new name for subsequent commands.
                    generator = cmd.name
                else:
                    assert False, 'Invalid ALTER GENERATOR command: %s' % \
                        (repr(cmd),)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.InitModels):
        if not core.bayesdb_has_generator_default(bdb, phrase.generator):
            raise BQLError(bdb, 'No such generator: %s' % (phrase.generator, ))
        generator_id = core.bayesdb_get_generator_default(
            bdb, phrase.generator)
        modelnos = range(phrase.nmodels)
        model_config = None  # XXX For now.

        with bdb.savepoint():
            # Find the model numbers.  Omit existing ones for
            # ifnotexists; reject existing ones otherwise.
            if phrase.ifnotexists:
                modelnos = set(modelno for modelno in modelnos
                               if not core.bayesdb_generator_has_model(
                                   bdb, generator_id, modelno))
            else:
                existing = set(modelno for modelno in modelnos
                               if core.bayesdb_generator_has_model(
                                   bdb, generator_id, modelno))
                if 0 < len(existing):
                    raise BQLError(
                        bdb, 'Generator %s already has models: %s' %
                        (repr(phrase.generator), sorted(existing)))

            # Stop now if there's nothing to initialize.
            if len(modelnos) == 0:
                return

            # Create the bayesdb_generator_model records.
            modelnos = sorted(modelnos)
            insert_model_sql = '''
                INSERT INTO bayesdb_generator_model
                    (generator_id, modelno, iterations)
                    VALUES (:generator_id, :modelno, :iterations)
            '''
            for modelno in modelnos:
                bdb.sql_execute(
                    insert_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                        'iterations': 0,
                    })

            # Do metamodel-specific initialization.
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            metamodel.initialize_models(bdb, generator_id, modelnos,
                                        model_config)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.AnalyzeModels):
        if not phrase.wait:
            raise NotImplementedError('No background analysis -- use WAIT.')
        # WARNING: It is the metamodel's responsibility to work in a
        # transaction.
        #
        # WARNING: It is the metamodel's responsibility to update the
        # iteration count in bayesdb_generator_model records.
        #
        # We do this so that the metamodel can save incremental
        # progress in case of ^C in the middle.
        #
        # XXX Put these warning somewhere more appropriate.
        if not core.bayesdb_has_generator_default(bdb, phrase.generator):
            raise BQLError(bdb, 'No such generator: %s' % (phrase.generator, ))
        generator_id = core.bayesdb_get_generator_default(
            bdb, phrase.generator)
        metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
        # XXX Should allow parameters for iterations and ckpt/iter.
        metamodel.analyze_models(bdb,
                                 generator_id,
                                 modelnos=phrase.modelnos,
                                 iterations=phrase.iterations,
                                 max_seconds=phrase.seconds,
                                 ckpt_iterations=phrase.ckpt_iterations,
                                 ckpt_seconds=phrase.ckpt_seconds)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.DropModels):
        with bdb.savepoint():
            generator_id = core.bayesdb_get_generator_default(
                bdb, phrase.generator)
            metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
            modelnos = None
            if phrase.modelnos is not None:
                lookup_model_sql = '''
                    SELECT COUNT(*) FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                '''
                modelnos = sorted(list(phrase.modelnos))
                for modelno in modelnos:
                    cursor = bdb.sql_execute(lookup_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                    })
                    if cursor_value(cursor) == 0:
                        raise BQLError(
                            bdb, 'No such model'
                            ' in generator %s: %s' %
                            (repr(phrase.generator), repr(modelno)))
            metamodel.drop_models(bdb, generator_id, modelnos=modelnos)
            if modelnos is None:
                drop_models_sql = '''
                    DELETE FROM bayesdb_generator_model WHERE generator_id = ?
                '''
                bdb.sql_execute(drop_models_sql, (generator_id, ))
            else:
                drop_model_sql = '''
                    DELETE FROM bayesdb_generator_model
                        WHERE generator_id = :generator_id
                        AND modelno = :modelno
                '''
                for modelno in modelnos:
                    bdb.sql_execute(drop_model_sql, {
                        'generator_id': generator_id,
                        'modelno': modelno,
                    })
        return empty_cursor(bdb)

    assert False  # XXX
Example #35
0
def bql_predict(bdb, generator_id, modelno, colno, rowid, threshold,
        numsamples=None):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    return metamodel.predict(bdb, generator_id, modelno, colno, rowid,
        threshold, numsamples=numsamples)
Example #36
0
 def cc(self, bdb, genid):
     return core.bayesdb_generator_metamodel(bdb, self.cc_id(bdb, genid))
Example #37
0
 def generator_predprob(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     return metamodel.logpdf_joint(bdb, generator_id, modelnos, fresh_rowid,
                                   cgpm_targets, cgpm_constraints)
Example #38
0
 def generator_depprob(generator_id):
     metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
     return metamodel.column_dependence_probability(bdb, generator_id, None,
                                                    colno0, colno1)
Example #39
0
                    total_changes = bdb._sqlite3.totalchanges()
                    bdb.sql_execute(update_column_sql, {
                        'table': table,
                        'old': cmd.old,
                        'new': cmd.new,
                    })
                    assert bdb._sqlite3.totalchanges() - total_changes == 1
                    # ...except metamodels may have the (case-folded)
                    # name cached.
                    if old_folded != new_folded:
                        generators_sql = '''
                            SELECT id FROM bayesdb_generator WHERE tabname = ?
                        '''
                        cursor = bdb.sql_execute(generators_sql, (table, ))
                        for (generator_id, ) in cursor:
                            metamodel = core.bayesdb_generator_metamodel(
                                bdb, generator_id)
                            metamodel.rename_column(bdb, generator_id,
                                                    old_folded, new_folded)
                else:
                    assert False, 'Invalid alter table command: %s' % \
                        (cmd,)
        return empty_cursor(bdb)

    if isinstance(phrase, ast.GuessSchema):
        if not core.bayesdb_has_table(bdb, phrase.table):
            raise BQLError(bdb, 'No such table : %s' % phrase.table)
        schema = guess.guess_to_schema(guess.bayesdb_guess_stattypes, bdb,
                                       phrase.table)
        # Print schema to console, so user can edit it and/or copy/paste it into
        # the schema definition when creating a population.
        print schema
Example #40
0
def bayesdb_insertmany(bdb, generator_id, rows):
    """Notify a generator that rows have been inserted into its table."""
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    metamodel.insertmany(bdb, generator_id, rows)
Example #41
0
def bql_column_mutual_information(bdb, generator_id, modelno, colno0, colno1,
        numsamples=None):
    metamodel = core.bayesdb_generator_metamodel(bdb, generator_id)
    return metamodel.column_mutual_information(bdb, generator_id, modelno,
        colno0, colno1, numsamples=numsamples)