Exemplo n.º 1
0
def range_for_material_objtype(objtype: s_objtypes.ObjectType,
                               path_id: irast.PathId,
                               *,
                               include_overlays: bool = True,
                               env: context.Environment) -> pgast.BaseRangeVar:

    from . import pathctx  # XXX: fix cycle

    objtype = objtype.material_type(env.schema)
    objtype_name = objtype.get_name(env.schema)

    table_schema_name, table_name = common.get_backend_name(env.schema,
                                                            objtype,
                                                            catenate=False)

    if objtype_name.module == 'schema':
        # Redirect all queries to schema tables to edgedbss
        table_schema_name = 'edgedbss'

    relation = pgast.Relation(
        schemaname=table_schema_name,
        name=table_name,
        path_id=path_id,
    )

    rvar = pgast.RangeVar(
        relation=relation,
        alias=pgast.Alias(aliasname=env.aliases.get(objtype_name.name)))

    overlays = env.rel_overlays.get(objtype_name)
    if overlays and include_overlays:
        set_ops = []

        qry = pgast.SelectStmt()
        qry.from_clause.append(rvar)
        pathctx.put_path_value_rvar(qry, path_id, rvar, env=env)
        pathctx.put_path_bond(qry, path_id)

        set_ops.append(('union', qry))

        for op, cte in overlays:
            rvar = pgast.RangeVar(
                relation=cte,
                alias=pgast.Alias(aliasname=env.aliases.get(hint=cte.name)))

            qry = pgast.SelectStmt(from_clause=[rvar], )

            pathctx.put_path_value_rvar(qry, path_id, rvar, env=env)
            pathctx.put_path_bond(qry, path_id)

            if op == 'replace':
                op = 'union'
                set_ops = []

            set_ops.append((op, qry))

        rvar = range_from_queryset(set_ops, objtype, env=env)

    return rvar
Exemplo n.º 2
0
def table_from_ptrcls(ptrcls: s_links.Link, *,
                      env: context.Environment) -> pgast.RangeVar:
    """Return a Table corresponding to a given Link."""
    table_schema_name, table_name = common.get_table_name(ptrcls,
                                                          catenate=False)

    pname = ptrcls.shortname

    if pname.module == 'schema':
        # Redirect all queries to schema tables to edgedbss
        table_schema_name = 'edgedbss'

    relation = pgast.Relation(schemaname=table_schema_name, name=table_name)

    rvar = pgast.RangeVar(
        relation=relation,
        alias=pgast.Alias(aliasname=env.aliases.get(pname.name)))

    return rvar
Exemplo n.º 3
0
def process_link_update(
        ir_stmt: irast.MutatingStmt, ir_expr: irast.Base, props_only: bool,
        wrapper: pgast.Query, dml_cte: pgast.CommonTableExpr,
        iterator_cte: pgast.CommonTableExpr, *,
        ctx: context.CompilerContextLevel) -> typing.Optional[pgast.Query]:
    """Perform updates to a link relation as part of a DML statement.

    :param ir_stmt:
        IR of the statement.
    :param ir_expr:
        IR of the INSERT/UPDATE body element.
    :param props_only:
        Whether this link update only touches link properties.
    :param wrapper:
        Top-level SQL query.
    :param dml_cte:
        CTE representing the SQL INSERT or UPDATE to the main
        relation of the Object.
    :param iterator_cte:
        CTE representing the iterator range in the FOR clause of the
        EdgeQL DML statement.
    """
    toplevel = ctx.toplevel_stmt

    edgedb_ptr_tab = pgast.RangeVar(
        relation=pgast.Relation(schemaname='edgedb', name='pointer'),
        alias=pgast.Alias(aliasname=ctx.env.aliases.get(hint='ptr')))

    ltab_alias = edgedb_ptr_tab.alias.aliasname

    rptr = ir_expr.rptr
    ptrcls = rptr.ptrcls
    target_is_scalar = isinstance(ptrcls.target, s_scalars.ScalarType)

    path_id = rptr.source.path_id.extend(ptrcls, rptr.direction,
                                         rptr.target.scls)

    # The links in the dml class shape have been derived,
    # but we must use the correct specialized link class for the
    # base material type.
    mptrcls = ptrcls.material_type()

    # Lookup link class id by link name.
    lname_to_id = pgast.CommonTableExpr(query=pgast.SelectStmt(
        from_clause=[edgedb_ptr_tab],
        target_list=[
            pgast.ResTarget(val=pgast.ColumnRef(name=[ltab_alias, 'id']))
        ],
        where_clause=astutils.new_binop(
            lexpr=pgast.ColumnRef(name=[ltab_alias, 'name']),
            rexpr=pgast.Constant(val=mptrcls.name),
            op=ast.ops.EQ)),
                                        name=ctx.env.aliases.get(hint='lid'))

    lname_to_id_rvar = pgast.RangeVar(relation=lname_to_id)
    toplevel.ctes.append(lname_to_id)

    target_rvar = dbobj.range_for_ptrcls(mptrcls,
                                         '>',
                                         include_overlays=False,
                                         env=ctx.env)
    target_alias = target_rvar.alias.aliasname

    target_tab_name = (target_rvar.relation.schemaname,
                       target_rvar.relation.name)

    tab_cols = dbobj.cols_for_pointer(mptrcls, env=ctx.env)

    dml_cte_rvar = pgast.RangeVar(
        relation=dml_cte,
        alias=pgast.Alias(aliasname=ctx.env.aliases.get('m')))

    col_data = {
        'ptr_item_id':
        pgast.ColumnRef(name=[lname_to_id.name, 'id']),
        'std::source':
        pathctx.get_rvar_path_identity_var(dml_cte_rvar,
                                           ir_stmt.subject.path_id,
                                           env=ctx.env)
    }

    # Drop all previous link records for this source.
    delcte = pgast.CommonTableExpr(query=pgast.DeleteStmt(
        relation=target_rvar,
        where_clause=astutils.new_binop(
            lexpr=col_data['std::source'],
            op=ast.ops.EQ,
            rexpr=pgast.ColumnRef(name=[target_alias, 'std::source'])),
        using_clause=[dml_cte_rvar],
        returning_list=[
            pgast.ResTarget(val=pgast.ColumnRef(
                name=[target_alias, pgast.Star()]))
        ]),
                                   name=ctx.env.aliases.get(hint='d'))

    pathctx.put_path_value_rvar(delcte.query,
                                path_id.ptr_path(),
                                target_rvar,
                                env=ctx.env)

    # Record the effect of this removal in the relation overlay
    # context to ensure that the RETURNING clause potentially
    # referencing this link yields the expected results.
    overlays = ctx.env.rel_overlays[ptrcls.shortname]
    overlays.append(('except', delcte))
    toplevel.ctes.append(delcte)

    # Turn the IR of the expression on the right side of :=
    # into a subquery returning records for the link table.
    data_cte, specified_cols = process_link_values(ir_stmt,
                                                   ir_expr,
                                                   target_tab_name,
                                                   tab_cols,
                                                   col_data,
                                                   dml_cte_rvar,
                                                   [lname_to_id_rvar],
                                                   props_only,
                                                   target_is_scalar,
                                                   iterator_cte,
                                                   ctx=ctx)

    toplevel.ctes.append(data_cte)

    data_select = pgast.SelectStmt(
        target_list=[
            pgast.ResTarget(val=pgast.ColumnRef(
                name=[data_cte.name, pgast.Star()]))
        ],
        from_clause=[pgast.RangeVar(relation=data_cte)])

    # Inserting rows into the link table may produce cardinality
    # constraint violations, since the INSERT into the link table
    # is executed in the snapshot where the above DELETE from
    # the link table is not visible.  Hence, we need to use
    # the ON CONFLICT clause to resolve this.
    conflict_cols = ['std::source', 'std::target', 'ptr_item_id']
    conflict_inference = []
    conflict_exc_row = []

    for col in conflict_cols:
        conflict_inference.append(pgast.ColumnRef(name=[col]))
        conflict_exc_row.append(pgast.ColumnRef(name=['excluded', col]))

    conflict_data = pgast.SelectStmt(
        target_list=[
            pgast.ResTarget(val=pgast.ColumnRef(
                name=[data_cte.name, pgast.Star()]))
        ],
        from_clause=[pgast.RangeVar(relation=data_cte)],
        where_clause=astutils.new_binop(
            lexpr=pgast.ImplicitRowExpr(args=conflict_inference),
            rexpr=pgast.ImplicitRowExpr(args=conflict_exc_row),
            op='='))

    cols = [pgast.ColumnRef(name=[col]) for col in specified_cols]
    updcte = pgast.CommonTableExpr(
        name=ctx.env.aliases.get(hint='i'),
        query=pgast.InsertStmt(
            relation=target_rvar,
            select_stmt=data_select,
            cols=cols,
            on_conflict=pgast.OnConflictClause(
                action='update',
                infer=pgast.InferClause(index_elems=conflict_inference),
                target_list=[
                    pgast.MultiAssignRef(columns=cols, source=conflict_data)
                ]),
            returning_list=[
                pgast.ResTarget(val=pgast.ColumnRef(name=[pgast.Star()]))
            ]))

    pathctx.put_path_value_rvar(updcte.query,
                                path_id.ptr_path(),
                                target_rvar,
                                env=ctx.env)

    # Record the effect of this insertion in the relation overlay
    # context to ensure that the RETURNING clause potentially
    # referencing this link yields the expected results.
    overlays = ctx.env.rel_overlays[ptrcls.shortname]
    overlays.append(('union', updcte))

    toplevel.ctes.append(updcte)

    return data_cte
Exemplo n.º 4
0
def process_insert_body(ir_stmt: irast.MutatingStmt, wrapper: pgast.Query,
                        insert_cte: pgast.CommonTableExpr,
                        insert_rvar: pgast.BaseRangeVar, *,
                        ctx: context.CompilerContextLevel) -> None:
    """Generate SQL DML CTEs from an InsertStmt IR.

    :param ir_stmt:
        IR of the statement.
    :param wrapper:
        Top-level SQL query.
    :param insert_cte:
        CTE representing the SQL INSERT to the main relation of the Object.
    """
    cols = [pgast.ColumnRef(name=['std::__type__'])]
    select = pgast.SelectStmt(target_list=[])
    values = select.target_list

    # The main INSERT query of this statement will always be
    # present to insert at least the std::id and std::__type__
    # links.
    insert_stmt = insert_cte.query

    insert_stmt.cols = cols
    insert_stmt.select_stmt = select

    if ir_stmt.parent_stmt is not None:
        iterator_set = ir_stmt.parent_stmt.iterator_stmt
    else:
        iterator_set = None

    if iterator_set is not None:
        with ctx.substmt() as ictx:
            ictx.path_scope = ictx.path_scope.new_child()
            ictx.path_scope[iterator_set.path_id] = ictx.rel
            clauses.compile_iterator_expr(ictx.rel, iterator_set, ctx=ictx)
            ictx.rel.path_id = iterator_set.path_id
            pathctx.put_path_bond(ictx.rel, iterator_set.path_id)
            iterator_cte = pgast.CommonTableExpr(
                query=ictx.rel, name=ctx.env.aliases.get('iter'))
            ictx.toplevel_stmt.ctes.append(iterator_cte)
        iterator_rvar = dbobj.rvar_for_rel(iterator_cte, env=ctx.env)
        relctx.include_rvar(select,
                            iterator_rvar,
                            path_id=ictx.rel.path_id,
                            ctx=ctx)
        iterator_id = pathctx.get_path_identity_var(select,
                                                    iterator_set.path_id,
                                                    env=ctx.env)
    else:
        iterator_cte = None
        iterator_id = None

    values.append(
        pgast.ResTarget(val=pgast.SelectStmt(
            target_list=[pgast.ResTarget(val=pgast.ColumnRef(name=['id']))],
            from_clause=[
                pgast.RangeVar(relation=pgast.Relation(name='objecttype',
                                                       schemaname='edgedb'))
            ],
            where_clause=astutils.new_binop(
                op=ast.ops.EQ,
                lexpr=pgast.ColumnRef(name=['name']),
                rexpr=pgast.Constant(val=ir_stmt.subject.scls.shortname)))))

    external_inserts = []
    tuple_elements = []
    parent_link_props = []

    with ctx.newrel() as subctx:
        subctx.rel = select
        subctx.rel_hierarchy[select] = insert_stmt

        subctx.expr_exposed = False
        subctx.shape_format = context.ShapeFormat.FLAT

        if iterator_cte is not None:
            subctx.path_scope = ctx.path_scope.new_child()
            subctx.path_scope[iterator_cte.query.path_id] = select

        # Process the Insert IR and separate links that go
        # into the main table from links that are inserted into
        # a separate link table.
        for shape_el in ir_stmt.subject.shape:
            rptr = shape_el.rptr
            ptrcls = rptr.ptrcls.material_type()

            if (ptrcls.is_link_property()
                    and rptr.source.path_id != ir_stmt.subject.path_id):
                parent_link_props.append(shape_el)
                continue

            ptr_info = pg_types.get_pointer_storage_info(
                ptrcls,
                schema=subctx.env.schema,
                resolve_type=True,
                link_bias=False)

            props_only = False

            # First, process all local link inserts.
            if ptr_info.table_type == 'ObjectType':
                props_only = True
                field = pgast.ColumnRef(name=[ptr_info.column_name])
                cols.append(field)

                insvalue = insert_value_for_shape_element(insert_stmt,
                                                          wrapper,
                                                          ir_stmt,
                                                          shape_el,
                                                          iterator_id,
                                                          ptr_info=ptr_info,
                                                          ctx=subctx)

                tuple_el = astutils.tuple_element_for_shape_el(shape_el, field)
                tuple_elements.append(tuple_el)
                values.append(pgast.ResTarget(val=insvalue))

            ptr_info = pg_types.get_pointer_storage_info(ptrcls,
                                                         resolve_type=False,
                                                         link_bias=True)

            if ptr_info and ptr_info.table_type == 'link':
                external_inserts.append((shape_el, props_only))

        if iterator_cte is not None:
            cols.append(pgast.ColumnRef(name=['__edb_token']))

            values.append(pgast.ResTarget(val=iterator_id))

            pathctx.put_path_identity_var(insert_stmt,
                                          iterator_set.path_id,
                                          cols[-1],
                                          force=True,
                                          env=subctx.env)

            pathctx.put_path_bond(insert_stmt, iterator_set.path_id)

    toplevel = ctx.toplevel_stmt
    toplevel.ctes.append(insert_cte)

    # Process necessary updates to the link tables.
    for shape_el, props_only in external_inserts:
        process_link_update(ir_stmt,
                            shape_el,
                            props_only,
                            wrapper,
                            insert_cte,
                            iterator_cte,
                            ctx=ctx)

    if parent_link_props:
        prop_elements = []

        with ctx.newscope() as scopectx:
            scopectx.rel = wrapper

            for shape_el in parent_link_props:
                rptr = shape_el.rptr
                scopectx.path_scope[rptr.source.path_id] = wrapper
                pathctx.put_path_rvar_if_not_exists(wrapper,
                                                    rptr.source.path_id,
                                                    insert_rvar,
                                                    aspect='value',
                                                    env=scopectx.env)
                dispatch.compile(shape_el, ctx=scopectx)
                tuple_el = astutils.tuple_element_for_shape_el(shape_el, None)
                prop_elements.append(tuple_el)

        valtuple = pgast.TupleVar(elements=prop_elements, named=True)
        pathctx.put_path_value_var(wrapper,
                                   ir_stmt.subject.path_id,
                                   valtuple,
                                   force=True,
                                   env=ctx.env)