Types and Domains

The dbtype module defines seven classes, DbType derived from DbSchemaObject, BaseType, Composite, Enum, Domain and Range derived from DbType, and TypeDict derived from and DbObjectDict.

Database Type

Class DbType is derived from DbSchemaObject and represents a SQL type or domain as defined in the Postgres pg_type catalog.

class pyrseas.dbobject.dbtype.DbType(name, schema, description, owner, privileges)

A user-defined type, such as a composite, domain or enum

Base Type

BaseType is derived from DbType and represents a Postgres user-defined base type.

The map returned by to_map() and expected as argument by TypeDict.from_map() has the following structure (not all fields need be present):

{'type t1':
    {'alignment': 'double',
     'analyze': 'analyze_func',
     'category': 'U',
     'delimiter': ',',
     'input': 'input_func',
     'internallength': 'variable',
     'output': 'output_func',
     'preferred': 'true',
     'receive': 'receive_func',
     'send': 'send_func',
     'storage': 'plain'
     'typmod_in': 'typmod_in_func',
     'typmod_out': 'typmod_out_func'
    }
}
class pyrseas.dbobject.dbtype.BaseType(name, schema, description, owner, privileges, input, output, receive=None, send=None, typmod_in=None, typmod_out=None, analyze=None, internallength=1, alignment=None, storage=None, delimiter=', ', category=None, preferred=False, oid=None)

A base type

BaseType.to_map(db, no_owner, no_privs)

Convert a type to a YAML-suitable format

Parameters:no_owner – exclude type owner information
Returns:dictionary
BaseType.create(obj, *args, **kwargs)

Return SQL statements to CREATE the base type

Returns:SQL statements
BaseType.drop()

Generate SQL to drop the type (and related functions)

Returns:list of SQL statements

Composite

Composite is derived from DbType and represents a standalone composite type.

class pyrseas.dbobject.dbtype.Composite(name, schema, description, owner, privileges, oid=None)

A composite type

Composite.to_map(db, no_owner, no_privs)

Convert a type to a YAML-suitable format

Parameters:no_owner – exclude type owner information
Returns:dictionary
Composite.create(obj, *args, **kwargs)

Return SQL statements to CREATE the composite type

Returns:SQL statements
Composite.alter(intype)

Generate SQL to transform an existing composite type

Parameters:intype – the new composite type
Returns:list of SQL statements

Compares the type to an input type and generates SQL statements to transform it into the one represented by the input.

Enum

Enum is derived from DbType and represents an enumerated type.

class pyrseas.dbobject.dbtype.Enum(name, schema, description, owner, privileges, labels, oid=None)

An enumerated type definition

Enum.create(obj, *args, **kwargs)

Return SQL statements to CREATE the enum

Returns:SQL statements

Domain

Domain is derived from DbType and represents a domain.

class pyrseas.dbobject.dbtype.Domain(name, schema, description, owner, privileges, type, not_null=False, default=None, oid=None)

A domain definition

Domain.to_map(db, no_owner, no_privs)

Convert a domain to a YAML-suitable format

Parameters:no_owner – exclude domain owner information
Returns:dictionary
Domain.create(obj, *args, **kwargs)

Return SQL statements to CREATE the domain

Returns:SQL statements

Range

Range is derived from DbType and represents a Postgres range type.

class pyrseas.dbobject.dbtype.Range(name, schema, description, owner, privileges, subtype, canonical=None, subtype_diff=None, oid=None)

A range type definition

Range.to_map(db, no_owner, no_privs)

Convert a range type to a YAML-suitable format

Parameters:no_owner – exclude type owner information
Returns:dictionary
Range.create(obj, *args, **kwargs)

Return SQL statements to CREATE the range

Returns:SQL statements
Range.alter(intype, no_owner=False)

Generate SQL to transform an existing range type

Parameters:intype – the new range type
Returns:list of SQL statements

Compares the range to an input range and generates SQL statements to transform it into the one represented by the input.

Type Dictionary

TypeDict is derived from DbObjectDict. It is a dictionary that represents the collection of domains and enums in a database.

class pyrseas.dbobject.dbtype.TypeDict(dbconn=None)

The collection of user-defined types in a database

TypeDict.from_map(schema, inobjs, newdb)

Initalize the dictionary of types by converting the input map

Parameters:
  • schema – schema owning the types
  • inobjs – YAML map defining the schema objects
  • newdb – collection of dictionaries defining the database