Tables, Views and Sequences

module: pyrseas.dbobject.table

The table and view modules define six classes, DbClass derived from DbSchemaObject, classes Sequence, Table and View derived from DbClass, MaterializedView derived from View, and ClassDict, derived from DbObjectDict.

Database Class

Class DbClass is derived from ~pyrseas.dbobject.DbSchemaObject and represents a table, view or sequence as defined in the Postgres pg_class catalog.

autoclass: DbClass

Sequence

Class Sequence is derived from DbClass and represents a sequence generator. Its keylist attributes are the schema name and the sequence name.

The map returned by to_map and expected as argument by ClassDict.from_map has the following structure:

{'sequence seq1':
    {'cache_value': 1,
     'data_type': 'integer',
     'increment_by': 1,
     'max_value': None,
     'min_value': None,
     'owner_column': 'c1',
     'owner_table': 't1',
     'start_value': 1
    }
}
autoclass: Sequence

automethod: Sequence.get_attrs

automethod: Sequence.get_dependent_table

automethod: Sequence.to_map

automethod: Sequence.create

automethod: Sequence.add_owner

automethod: Sequence.alter

automethod: Sequence.drop

Table

Class Table is derived from DbClass and represents a database table. Its keylist attributes are the schema name and the table name.

The map returned by to_map and expected as argument by ClassDict.from_map has a structure similar to the following:

{'table t1':
    {'columns':
        [
        {'c1': {'type': 'integer', 'not_null': True}},
        {'c2': {'type': 'text'}},
        {'c3': {'type': 'smallint'}},
        {'c4': {'type': 'date', 'default': 'now()'}}
        ],
     'description': "this is the comment for table t1",
     'primary_key':
        {'t1_prim_key':
            {'columns': ['c1', 'c2']}
        },
     'foreign_keys':
        {'t1_fgn_key1':
            {'columns': ['c2', 'c3'],
              'references':
                  {'table': 't2', 'columns': ['pc2', 'pc1']}
            },
         't1_fgn_key2':
            {'columns': ['c2'],
             'references': {'table': 't3', 'columns': ['qc1']}
            }
        },
     'unique_constraints': {...},
     'indexes': {...}
    }
}

The values for unique_constraints and indexes follow a pattern similar to primary_key, but there can be more than one such specification.

autoclass: Table

automethod: Table.column_names

automethod: Table.to_map

automethod: Table.create

automethod: Table.drop

automethod: Table.diff_options

automethod: Table.alter

automethod: Table.alter_drop_columns

automethod: Table.data_export

automethod: Table.data_import

Class Dictionary

Class ClassDict is derived from ~pyrseas.dbobject.DbObjectDict and represents the collection of tables, views and sequences in a database.

autoclass: ClassDict

automethod: ClassDict.from_map

module: pyrseas.dbobject.view

View

Class View is derived from DbClass and represents a database view. Its keylist attributes are the schema name and the view name.

The map returned by to_map and expected as argument by ClassDict.from_map has a structure similar to the following:

{'view v1':
    {'definition': " SELECT ...;",
     'description': "this is the comment for view v1"
    }
}
autoclass: View

automethod: View.to_map

automethod: View.create

automethod: View.alter

Materialized View

Class MaterializedView is derived from View and represents a materialized view. Its keylist attributes are the schema name and the view name.

autoclass: MaterializedView

automethod: MaterializedView.to_map

automethod: MaterializedView.create