class ReplicateTable(object): def __init__(self): self.error = ErrorHandling() self.mysql = MySQLConnector() self.execute = Execute() self.table = ConstructReplicationQuery() def replicate_table(self, db, source_table_name, destination_table_name): """ :param db: :param source_table_name: :param destination_table_name: """ self.error.warn("making TABLE %s, an exact copy of TABLE %s..." % (destination_table_name, source_table_name)) self.error.warn("connecting to DATABASE %s..." % db) (db_conn, db_cursor, dict_cursor) = self.mysql.db_connect(db) self.error.warn("cloning structure of table...") clone_query = self.table.construct_replication_query(db_conn, source_table_name, destination_table_name) self.execute.execute_(db, db_cursor, clone_query, True) self.error.warn("populating newly created table, TABLE %s" % destination_table_name) populate_query = """INSERT INTO " + destination_table_name + " SELECT * FROM """ + source_table_name self.execute.execute_(db, db_cursor, populate_query, True) self.error.warn("finished replicating table!")
class QuickExecute(object): def __init__(self): self.mysql = MySQLConnector() self.execute = Execute() def quick_execute(self, db, query, warn=False): """ This method performs the db connect and execute in the same call. """ (con, cursor_, dict_cursor) = self.mysql.db_connect(db) return self.execute.execute_(db, cursor_, query, warn)
class RandomSubset(object): def __init__(self): self.mysql = MySQLConnector() self.error = ErrorHandling() self.execute_one_col = ExecuteGetListOneColumn() self.execute = Execute() def random_subset_table(self, db, source_table_name, destination_table_name, field, percent=.10, distinct=True): """ This method selects a random sample of records from source table to destination table :param db: :param source_table_name: :param destination_table_name: :param field: :param percent: :param distinct: """ self.error.warn("making TABLE %s, a %2.2f percent random subset of TABLE %s on unique key %s..." % ( destination_table_name, percent, source_table_name, field)) self.error.warn("connecting to DATABASE %s..." % db) (db_conn, db_cursor, dict_cursor) = self.mysql.db_connect(db) self.error.warn("removing destination table if it exists...") sql = 'DROP TABLE IF EXISTS %s' % destination_table_name self.execute.execute_(db, db_cursor, sql, True) self.error.warn("cloning structure of table...") sql = 'CREATE TABLE %s LIKE %s' % (destination_table_name, source_table_name) self.execute.execute_(db, db_cursor, sql, True) is_distinct_text = ' distinct' if distinct else '' self.error.warn('grabbing a%s subset (%2.6f percent) of the keys on which to base the new table' % ( is_distinct_text, 100 * percent)) sql = 'SELECT DISTINCT(%s) FROM %s' % (field, source_table_name) if distinct else 'SELECT %s FROM %s' % ( field, source_table_name) unique_key_list = self.execute_one_col.execute_get_list_one_col(db, db_cursor, sql, True) self.error.warn(str(unique_key_list[1:5])) new_keys = sample(unique_key_list, int(floor(len(unique_key_list) * percent))) new_keys = map(str, new_keys) self.error.warn("populating newly created table, TABLE %s" % destination_table_name) populate_query = "INSERT INTO %s SELECT * FROM %s WHERE %s IN (%s)" % ( destination_table_name, source_table_name, field, ','.join(new_keys)) self.execute.execute_(db, db_cursor, populate_query, False) self.error.warn("finished making TABLE %s, a %2.2f percent random subset of TABLE %s on unique key %s!" % ( destination_table_name, percent, source_table_name, field))