sqlalchemy.dialects.postgresql.pg8000.PGDialect

class documentation

class PGDialect_pg8000(PGDialect):

Undocumented

Class Method	`dbapi`	Undocumented
Method	`__init__`	Undocumented
Method	`create_connect_args`	Build DB-API compatible connection arguments.
Method	`do_begin_twophase`	Begin a two phase transaction on the given connection.
Method	`do_commit_twophase`	Commit a two phase transaction on the given connection.
Method	`do_prepare_twophase`	Prepare a two phase transaction on the given connection.
Method	`do_recover_twophase`	Recover list of uncommitted prepared two phase transaction identifiers on the given connection.
Method	`do_rollback_twophase`	Rollback a two phase transaction on the given connection.
Method	`do_set_input_sizes`	invoke the cursor.setinputsizes() method with appropriate arguments
Method	`get_deferrable`	Undocumented
Method	`get_readonly`	Undocumented
Method	`is_disconnect`	Return True if the given DB-API error indicates an invalid connection
Method	`on_connect`	return a callable which sets up a newly created DBAPI connection.
Method	`set_client_encoding`	Undocumented
Method	`set_deferrable`	Undocumented
Method	`set_isolation_level`	Given a DBAPI connection, set its isolation level.
Method	`set_readonly`	Undocumented
Class Variable	`colspecs`	Undocumented
Class Variable	`default_paramstyle`	Undocumented
Class Variable	`description_encoding`	Undocumented
Class Variable	`driver`	Undocumented
Class Variable	`supports_sane_multi_rowcount`	Undocumented
Class Variable	`supports_server_side_cursors`	Undocumented
Class Variable	`supports_statement_cache`	indicates if this dialect supports caching.
Class Variable	`supports_unicode_binds`	Undocumented
Class Variable	`supports_unicode_statements`	Undocumented
Class Variable	`use_setinputsizes`	Undocumented
Instance Variable	`client_encoding`	Undocumented
Property	`_dbapi_version`	Undocumented

Inherited from PGDialect:

Method	`_get_column_info`	Undocumented
Method	`_get_default_schema_name`	Return the string name of the currently selected schema from the given connection.
Method	`_get_foreign_table_names`	Undocumented
Method	`_get_server_version_info`	Retrieve the server version info from the given connection.
Method	`_load_domains`	Undocumented
Method	`_load_enums`	Undocumented
Method	`_pg_index_any`	Undocumented
Method	`get_check_constraints`	Return information about check constraints in `table_name`.
Method	`get_columns`	Return information about columns in `table_name`.
Method	`get_foreign_keys`	Return information about foreign_keys in `table_name`.
Method	`get_indexes`	Return information about indexes in `table_name`.
Method	`get_isolation_level`	Given a DBAPI connection, return its isolation level.
Method	`get_pk_constraint`	Return information about the primary key constraint on table_name`.
Method	`get_schema_names`	Undocumented
Method	`get_sequence_names`	Return a list of all sequence names available in the database.
Method	`get_table_comment`	Return the "comment" for the table identified by `table_name`.
Method	`get_table_names`	Return a list of table names for `schema`.
Method	`get_table_oid`	Fetch the oid for schema.table_name.
Method	`get_unique_constraints`	Return information about unique constraints in `table_name`.
Method	`get_view_definition`	Return view definition.
Method	`get_view_names`	Return a list of all view names available in the database.
Method	`has_schema`	Undocumented
Method	`has_sequence`	Check the existence of a particular sequence in the database.
Method	`has_table`	For internal dialect use, check the existence of a particular table in the database.
Method	`has_type`	Undocumented
Method	`initialize`	Called during strategized creation of the dialect with a connection.
Class Variable	`_isolation_lookup`	Undocumented
Class Variable	`connection_characteristics`	Undocumented
Class Variable	`construct_arguments`	Optional set of argument specifiers for various SQLAlchemy constructs, typically schema items.
Class Variable	`max_identifier_length`	Undocumented
Class Variable	`name`	Undocumented
Class Variable	`postfetch_lastrowid`	Undocumented
Class Variable	`preexecute_autoincrement_sequences`	Undocumented
Class Variable	`reflection_options`	Undocumented
Class Variable	`sequences_optional`	Undocumented
Class Variable	`supports_alter`	Undocumented
Class Variable	`supports_comments`	Undocumented
Class Variable	`supports_default_metavalue`	dialect supports INSERT... VALUES (DEFAULT) syntax
Class Variable	`supports_default_values`	dialect supports INSERT... DEFAULT VALUES syntax
Class Variable	`supports_empty_insert`	dialect supports INSERT () VALUES ()
Class Variable	`supports_multivalues_insert`	Undocumented
Class Variable	`supports_native_boolean`	Undocumented
Class Variable	`supports_sane_rowcount`	Undocumented
Class Variable	`supports_sequences`	Undocumented
Instance Variable	`_backslash_escapes`	Undocumented
Instance Variable	`_json_deserializer`	Undocumented
Instance Variable	`_json_serializer`	Undocumented
Instance Variable	`_supports_create_index_concurrently`	Undocumented
Instance Variable	`_supports_drop_index_concurrently`	Undocumented
Instance Variable	`full_returning`	Undocumented
Instance Variable	`implicit_returning`	Undocumented
Instance Variable	`isolation_level`	Undocumented
Instance Variable	`supports_identity_columns`	Undocumented
Instance Variable	`supports_native_enum`	Undocumented
Instance Variable	`supports_smallserial`	Undocumented

Inherited from DefaultDialect (via PGDialect):

Class Method	`get_pool_class`	Undocumented
Class Method	`load_provisioning`	set up the provision.py module for this dialect.
Method	`connect`	Establish a connection using this dialect's DBAPI.
Method	`create_xid`	Create a random two-phase transaction ID.
Method	`denormalize_name`	convert the given name to a case insensitive identifier for the backend if it is an all-lowercase name.
Method	`do_begin`	Provide an implementation of `connection.begin()`, given a DB-API connection.
Method	`do_close`	Provide an implementation of `connection.close()`, given a DBAPI connection.
Method	`do_commit`	Provide an implementation of `connection.commit()`, given a DB-API connection.
Method	`do_execute`	Provide an implementation of `cursor.execute(statement, parameters)`.
Method	`do_execute_no_params`	Provide an implementation of `cursor.execute(statement)`.
Method	`do_executemany`	Provide an implementation of `cursor.executemany(statement, parameters)`.
Method	`do_release_savepoint`	Release the named savepoint on a connection.
Method	`do_rollback`	Provide an implementation of `connection.rollback()`, given a DB-API connection.
Method	`do_rollback_to_savepoint`	Rollback a connection to the named savepoint.
Method	`do_savepoint`	Create a savepoint with the given name.
Method	`get_default_isolation_level`	Given a DBAPI connection, return its isolation level, or a default isolation level if one cannot be retrieved.
Method	`get_driver_connection`	Returns the connection object as returned by the external driver package.
Method	`has_index`	Check the existence of a particular index name in the database.
Method	`normalize_name`	convert the given name to lowercase if it is detected as case insensitive.
Method	`reset_isolation_level`	Given a DBAPI connection, revert its isolation to the default.
Method	`type_descriptor`	Provide a database-specific `.TypeEngine` object, given the generic object which comes from the types module.
Class Variable	`dbapi_exception_translation_map`	mapping used in the extremely unusual case that a DBAPI's published exceptions don't actually have the __name__ that they are linked towards.
Instance Variable	`returns_unicode_strings`	Undocumented
Instance Variable	`type_compiler`	Undocumented
Method	`_check_max_identifier_length`	Perform a connection / server version specific check to determine the max_identifier_length.
Method	`_check_unicode_description`	Undocumented
Method	`_check_unicode_returns`	Undocumented
Method	`_ensure_has_table_connection`	Undocumented
Method	`_reset_characteristics`	Undocumented
Method	`_set_connection_characteristics`	Undocumented
Method	`do_ping`	Undocumented
Method	`get_dialect_pool_class`	Undocumented
Method	`set_connection_execution_options`	Undocumented
Method	`set_engine_execution_options`	Undocumented
Method	`validate_identifier`	Undocumented
Class Variable	`cte_follows_insert`	Undocumented
Class Variable	`default_sequence_base`	Undocumented
Class Variable	`engine_config_types`	Undocumented
Class Variable	`inline_comments`	Undocumented
Class Variable	`insert_executemany_returning`	Undocumented
Class Variable	`is_async`	Undocumented
Class Variable	`max_constraint_name_length`	Undocumented
Class Variable	`max_index_name_length`	Undocumented
Class Variable	`non_native_boolean_check_constraint`	Undocumented
Class Variable	`requires_name_normalize`	Undocumented
Class Variable	`server_side_cursors`	Undocumented
Class Variable	`supports_for_update_of`	Undocumented
Class Variable	`supports_is_distinct_from`	Undocumented
Class Variable	`supports_native_decimal`	Undocumented
Class Variable	`supports_schemas`	Undocumented
Class Variable	`supports_simple_order_by_label`	Undocumented
Class Variable	`supports_views`	Undocumented
Class Variable	`tuple_in_values`	Undocumented
Instance Variable	`_decoder`	Undocumented
Instance Variable	`_description_decoder`	Undocumented
Instance Variable	`_encoder`	Undocumented
Instance Variable	`_ischema`	Undocumented
Instance Variable	`_user_defined_max_identifier_length`	Undocumented
Instance Variable	`case_sensitive`	Undocumented
Instance Variable	`compiler_linting`	Undocumented
Instance Variable	`convert_unicode`	Undocumented
Instance Variable	`default_isolation_level`	Undocumented
Instance Variable	`default_schema_name`	Undocumented
Instance Variable	`encoding`	Undocumented
Instance Variable	`identifier_preparer`	Undocumented
Instance Variable	`label_length`	Undocumented
Instance Variable	`paramstyle`	Undocumented
Instance Variable	`positional`	Undocumented
Instance Variable	`server_version_info`	Undocumented
Property	`_dialect_specific_select_one`	Undocumented
Property	`_supports_statement_cache`	Undocumented
Property	`_type_memos`	Undocumented
Property	`dialect_description`	Undocumented
Property	`supports_sane_rowcount_returning`	True if this dialect supports sane rowcount even if RETURNING is in use.

Inherited from Dialect (via PGDialect, DefaultDialect):

Class Method	`engine_created`	A convenience hook called before returning the final `_engine.Engine`.
Class Method	`get_dialect_cls`	Given a URL, return the `.Dialect` that will be used.
Method	`get_temp_table_names`	Return a list of temporary table names on the given connection, if supported by the underlying backend.
Method	`get_temp_view_names`	Return a list of temporary view names on the given connection, if supported by the underlying backend.
Method	`on_connect_url`	return a callable which sets up a newly created DBAPI connection.
Class Variable	`_has_events`	Undocumented

@classmethod
def dbapi(cls):

overrides sqlalchemy.engine.default.DefaultDialect.dbapi

Undocumented

def __init__(self, client_encoding=None, **kwargs):

overrides sqlalchemy.databases.postgresql.PGDialect.__init__

Undocumented

def create_connect_args(self, url):

overrides sqlalchemy.engine.default.DefaultDialect.create_connect_args

Build DB-API compatible connection arguments.

Given a .URL object, returns a tuple consisting of a (*args, **kwargs) suitable to send directly to the dbapi's connect function. The arguments are sent to the .Dialect.connect method which then runs the DBAPI-level connect() function.

The method typically makes use of the .URL.translate_connect_args method in order to generate a dictionary of options.

The default implementation is:

def create_connect_args(self, url):
    opts = url.translate_connect_args()
    opts.update(url.query)
    return [[], opts]

See Also

.URL.translate_connect_args

Parameters
url	a `.URL` object
Returns
a tuple of `(args, *kwargs)` which will be passed to the `.Dialect.connect` method.

def do_begin_twophase(self, connection, xid):

overrides sqlalchemy.databases.postgresql.PGDialect.do_begin_twophase

Begin a two phase transaction on the given connection.

Parameters
connection	a `_engine.Connection`.
xid	xid

def do_commit_twophase(self, connection, xid, is_prepared=True, recover=False):

overrides sqlalchemy.databases.postgresql.PGDialect.do_commit_twophase

Commit a two phase transaction on the given connection.

Parameters
connection	a `_engine.Connection`.
xid	xid
is_prepared	whether or not `.TwoPhaseTransaction.prepare` was called.
recover	if the recover flag was passed.

def do_prepare_twophase(self, connection, xid):

overrides sqlalchemy.databases.postgresql.PGDialect.do_prepare_twophase

Prepare a two phase transaction on the given connection.

Parameters
connection	a `_engine.Connection`.
xid	xid

def do_recover_twophase(self, connection):

overrides sqlalchemy.databases.postgresql.PGDialect.do_recover_twophase

Recover list of uncommitted prepared two phase transaction identifiers on the given connection.

Parameters
connection	a `_engine.Connection`.

def do_rollback_twophase(self, connection, xid, is_prepared=True, recover=False):

overrides sqlalchemy.databases.postgresql.PGDialect.do_rollback_twophase

Rollback a two phase transaction on the given connection.

Parameters
connection	a `_engine.Connection`.
xid	xid
is_prepared	whether or not `.TwoPhaseTransaction.prepare` was called.
recover	if the recover flag was passed.

def do_set_input_sizes(self, cursor, list_of_tuples, context):

overrides sqlalchemy.engine.interfaces.Dialect.do_set_input_sizes

invoke the cursor.setinputsizes() method with appropriate arguments

This hook is called if the dialect.use_inputsizes flag is set to True. Parameter data is passed in a list of tuples (paramname, dbtype, sqltype), where paramname is the key of the parameter in the statement, dbtype is the DBAPI datatype and sqltype is the SQLAlchemy type. The order of tuples is in the correct parameter order.

New in version 1.4.

def get_deferrable(self, connection):

overrides sqlalchemy.databases.postgresql.PGDialect.get_deferrable

Undocumented

def get_readonly(self, connection):

overrides sqlalchemy.databases.postgresql.PGDialect.get_readonly

Undocumented

def is_disconnect(self, e, connection, cursor):

overrides sqlalchemy.engine.default.DefaultDialect.is_disconnect

Return True if the given DB-API error indicates an invalid connection

def on_connect(self):

overrides sqlalchemy.databases.postgresql.PGDialect.on_connect

return a callable which sets up a newly created DBAPI connection.

The callable should accept a single argument "conn" which is the DBAPI connection itself. The inner callable has no return value.

E.g.:

class MyDialect(default.DefaultDialect):
    # ...

    def on_connect(self):
        def do_on_connect(connection):
            connection.execute("SET SPECIAL FLAGS etc")

        return do_on_connect

This is used to set dialect-wide per-connection options such as isolation modes, Unicode modes, etc.

The "do_on_connect" callable is invoked by using the _events.PoolEvents.connect event hook, then unwrapping the DBAPI connection and passing it into the callable.

Changed in version 1.4: the on_connect hook is no longer called twice for the first connection of a dialect. The on_connect hook is still called before the _engine.Dialect.initialize method however.

Changed in version 1.4.3: the on_connect hook is invoked from a new method on_connect_url that passes the URL that was used to create the connect args. Dialects can implement on_connect_url instead of on_connect if they need the URL object that was used for the connection in order to get additional context.

If None is returned, no event listener is generated.

See Also

.Dialect.connect - allows the DBAPI connect() sequence itself to be controlled.

.Dialect.on_connect_url - supersedes .Dialect.on_connect to also receive the _engine.URL object in context.

Returns
a callable that accepts a single DBAPI connection as an argument, or None.

def set_client_encoding(self, connection, client_encoding):

Undocumented

def set_deferrable(self, connection, value):

overrides sqlalchemy.databases.postgresql.PGDialect.set_deferrable

Undocumented

def set_isolation_level(self, connection, level):

overrides sqlalchemy.databases.postgresql.PGDialect.set_isolation_level

Given a DBAPI connection, set its isolation level.

Note that this is a dialect-level method which is used as part of the implementation of the _engine.Connection and _engine.Engine isolation level facilities; these APIs should be preferred for most typical use cases.

See Also

_engine.Connection.get_isolation_level - view current level

_engine.Connection.default_isolation_level - view default level

:paramref:`.Connection.execution_options.isolation_level` - set per _engine.Connection isolation level

:paramref:`_sa.create_engine.isolation_level` - set per _engine.Engine isolation level

def set_readonly(self, connection, value):

overrides sqlalchemy.databases.postgresql.PGDialect.set_readonly

Undocumented

colspecs =

overrides sqlalchemy.databases.postgresql.PGDialect.colspecs

Undocumented

default_paramstyle: str =

overrides sqlalchemy.databases.postgresql.PGDialect.default_paramstyle

Undocumented

description_encoding =

overrides sqlalchemy.engine.default.DefaultDialect.description_encoding

Undocumented

driver: str =

Undocumented

supports_sane_multi_rowcount: bool =

overrides sqlalchemy.engine.default.DefaultDialect.supports_sane_multi_rowcount

Undocumented

supports_server_side_cursors: bool =

overrides sqlalchemy.engine.default.DefaultDialect.supports_server_side_cursors

Undocumented

supports_statement_cache: bool =

overrides sqlalchemy.databases.postgresql.PGDialect.supports_statement_cache

indicates if this dialect supports caching.

All dialects that are compatible with statement caching should set this flag to True directly on each dialect class and subclass that supports it. SQLAlchemy tests that this flag is locally present on each dialect subclass before it will use statement caching. This is to provide safety for legacy or new dialects that are not yet fully tested to be compliant with SQL statement caching.

New in version 1.4.5.

See Also

:ref:`engine_thirdparty_caching`

supports_unicode_binds: bool =

overrides sqlalchemy.engine.default.DefaultDialect.supports_unicode_binds

Undocumented

supports_unicode_statements: bool =

overrides sqlalchemy.engine.default.DefaultDialect.supports_unicode_statements

Undocumented

use_setinputsizes: bool =

overrides sqlalchemy.engine.default.DefaultDialect.use_setinputsizes

Undocumented

client_encoding =

Undocumented

@util.memoized_property
_dbapi_version =

Undocumented

sqlalchemy.dialects.postgresql.pg8000.PGDialect_pg8000

`sqlalchemy.dialects.postgresql.pg8000.PGDialect_pg8000`