django1/django/db/backends/postgresql_psycopg2/base.py

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"""
PostgreSQL database backend for Django.
Requires psycopg 2: http://initd.org/projects/psycopg2
"""
from django.conf import settings
from django.db.backends import (BaseDatabaseFeatures, BaseDatabaseWrapper,
BaseDatabaseValidation)
from django.db.backends.postgresql_psycopg2.operations import DatabaseOperations
from django.db.backends.postgresql_psycopg2.client import DatabaseClient
from django.db.backends.postgresql_psycopg2.creation import DatabaseCreation
from django.db.backends.postgresql_psycopg2.version import get_version
from django.db.backends.postgresql_psycopg2.introspection import DatabaseIntrospection
from django.db.backends.postgresql_psycopg2.schema import DatabaseSchemaEditor
from django.db.utils import InterfaceError
from django.utils.encoding import force_str
from django.utils.functional import cached_property
from django.utils.safestring import SafeText, SafeBytes
from django.utils.timezone import utc
try:
import psycopg2 as Database
import psycopg2.extensions
except ImportError as e:
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured("Error loading psycopg2 module: %s" % e)
DatabaseError = Database.DatabaseError
IntegrityError = Database.IntegrityError
psycopg2.extensions.register_type(psycopg2.extensions.UNICODE)
psycopg2.extensions.register_type(psycopg2.extensions.UNICODEARRAY)
psycopg2.extensions.register_adapter(SafeBytes, psycopg2.extensions.QuotedString)
psycopg2.extensions.register_adapter(SafeText, psycopg2.extensions.QuotedString)
def utc_tzinfo_factory(offset):
if offset != 0:
raise AssertionError("database connection isn't set to UTC")
return utc
class DatabaseFeatures(BaseDatabaseFeatures):
needs_datetime_string_cast = False
can_return_id_from_insert = True
has_real_datatype = True
can_defer_constraint_checks = True
has_select_for_update = True
has_select_for_update_nowait = True
has_bulk_insert = True
uses_savepoints = True
can_release_savepoints = True
supports_tablespaces = True
supports_transactions = True
can_introspect_ip_address_field = True
can_introspect_small_integer_field = True
can_distinct_on_fields = True
can_rollback_ddl = True
supports_combined_alters = True
nulls_order_largest = True
closed_cursor_error_class = InterfaceError
Fixed #16187 -- refactored ORM lookup system Allowed users to specify which lookups or transforms ("nested lookus") are available for fields. The implementation is now class based. Squashed commit of the following: commit fa7a7195f1952a9c8dea7f6e89ee13f81757eda7 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 18 10:53:24 2014 +0200 Added lookup registration API docs commit eb1c8ce164325e0d8641f14202e12486c70efdb6 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Tue Jan 14 18:59:36 2014 +0200 Release notes and other minor docs changes commit 11501c29c9352d17f22f3a0f59d3b805913dedcc Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 20:53:03 2014 +0200 Forgot to add custom_lookups tests in prev commit commit 83173b960ea7eb2b24d573f326be59948df33536 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 19:59:12 2014 +0200 Renamed Extract -> Transform commit 3b18d9f3a1bcdd93280f79654eba0efa209377bd Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 19:51:53 2014 +0200 Removed suggestion of temporary lookup registration from docs commit 21d0c7631c161fc0c67911480be5d3f13f1afa68 Merge: 2509006 f2dc442 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 09:38:23 2014 -0800 Merge pull request #2 from mjtamlyn/lookups_3 Reworked custom lookups docs. commit f2dc4429a1da04c858364972eea57a35a868dab4 Author: Marc Tamlyn <marc.tamlyn@gmail.com> Date: Sun Jan 12 13:15:05 2014 +0000 Reworked custom lookups docs. Mostly just formatting and rewording, but also replaced the example using ``YearExtract`` to use an example which is unlikely to ever be possible directly in the ORM. commit 250900650628d1f11beadb22814abd666029fb81 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 13:19:13 2014 +0200 Removed unused import commit 4fba5dfaa022653ffa72497258ffd8f8b7476f92 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 22:34:41 2014 +0200 Added docs to index commit 6d53963f375c77a1f287833b19b976d23f36c30b Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 22:10:24 2014 +0200 Dead code removal commit f9cc0390078e21f1ea5a7bc1f15b09f8f6b0904d Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 19:00:43 2014 +0200 A new try for docs commit 33aa18a6e3c831930bda0028222a26f9c1d96e66 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 14:57:12 2014 +0200 Renamed get_cols to get_group_by_cols commit c7d5f8661b7d364962bed2e6f81161c1b4f1bcc3 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 14:45:53 2014 +0200 Altered query string customization for backends vendors The new way is trying to call first method 'as_' + connection.vendor. If that doesn't exist, then call as_sql(). Also altered how lookup registration is done. There is now RegisterLookupMixin class that is used by Field, Extract and sql.Aggregate. This allows one to register lookups for extracts and aggregates in the same way lookup registration is done for fields. commit 90e7004ec14e15503f828cc9bde2a7dab593814d Merge: 66649ff f7c2c0a Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 13:21:01 2014 +0200 Merge branch 'master' into lookups_3 commit 66649ff891c7c73c7eecf6038c9a6802611b5d8a Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 13:16:01 2014 +0200 Some rewording in docs commit 31b8faa62714b4b6b6057a9f5cc106c4dd73caab Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 29 15:52:29 2013 +0200 Cleanup based on review comments commit 1016159f34674c0df871ed891cde72be8340bb5d Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 28 18:37:04 2013 +0200 Proof-of-concept fix for #16731 Implemented only for SQLite and PostgreSQL, and only for startswith and istartswith lookups. commit 193cd097ca8f2cc6a911e57b8e3fb726f96ee6a6 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 28 17:57:58 2013 +0200 Fixed #11722 -- iexact=F() produced invalid SQL commit 08ed3c3b49e100ed9019831e770c25c8f61b70f9 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 23:59:52 2013 +0200 Made Lookup and Extract available from django.db.models commit b99c8d83c972786c6fcd0e84c9e5cb08c1368300 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 23:06:29 2013 +0200 Fixed review notes by Loic commit 049eebc0703c151127f4f0265beceea7b8b39e72 Merge: ed8fab7 b80a835 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 22:53:10 2013 +0200 Merge branch 'master' into lookups_3 Conflicts: django/db/models/fields/__init__.py django/db/models/sql/compiler.py django/db/models/sql/query.py tests/null_queries/tests.py commit ed8fab7fe8867ff3eb801c3697a426478387bb2f Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 22:47:23 2013 +0200 Made Extracts aware of full lookup path commit 27a57b7aed91b2f346abc4a77da838bffa17c727 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 21:10:11 2013 +0200 Removed debugger import commit 074e0f5aca0572e368c11e6d2c73c9026e7d63d7 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 21:02:16 2013 +0200 GIS lookup support added commit 760e28e72bae475b442b026650969b0d182dbe53 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 20:04:31 2013 +0200 Removed usage of Constraint, used Lookup instead commit eac47766844b90e7d3269e7a8c012eee34ec0093 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 02:22:30 2013 +0200 Minor cleanup of Lookup API commit 2adf50428d59a783078b0da3d5d035106640c899 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 02:14:19 2013 +0200 Added documentation, polished implementation commit 32c04357a87e3727a34f8c5e6ec0114d1fbbb303 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Nov 30 23:10:15 2013 +0200 Avoid OrderedDict creation on lookup aggregate check commit 7c8b3a32cc17b4dbca160921d48125f1631e0df4 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Nov 30 23:04:34 2013 +0200 Implemented nested lookups But there is no support of using lookups outside filtering yet. commit 4d219d4cdef21d9c14e5d6b9299d583d1975fcba Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Wed Nov 27 22:07:30 2013 +0200 Initial implementation of custom lookups
2014-01-18 17:09:43 +08:00
has_case_insensitive_like = False
requires_sqlparse_for_splitting = False
class DatabaseWrapper(BaseDatabaseWrapper):
vendor = 'postgresql'
operators = {
'exact': '= %s',
'iexact': '= UPPER(%s)',
'contains': 'LIKE %s',
'icontains': 'LIKE UPPER(%s)',
'regex': '~ %s',
'iregex': '~* %s',
'gt': '> %s',
'gte': '>= %s',
'lt': '< %s',
'lte': '<= %s',
'startswith': 'LIKE %s',
'endswith': 'LIKE %s',
'istartswith': 'LIKE UPPER(%s)',
'iendswith': 'LIKE UPPER(%s)',
}
Fixed #16187 -- refactored ORM lookup system Allowed users to specify which lookups or transforms ("nested lookus") are available for fields. The implementation is now class based. Squashed commit of the following: commit fa7a7195f1952a9c8dea7f6e89ee13f81757eda7 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 18 10:53:24 2014 +0200 Added lookup registration API docs commit eb1c8ce164325e0d8641f14202e12486c70efdb6 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Tue Jan 14 18:59:36 2014 +0200 Release notes and other minor docs changes commit 11501c29c9352d17f22f3a0f59d3b805913dedcc Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 20:53:03 2014 +0200 Forgot to add custom_lookups tests in prev commit commit 83173b960ea7eb2b24d573f326be59948df33536 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 19:59:12 2014 +0200 Renamed Extract -> Transform commit 3b18d9f3a1bcdd93280f79654eba0efa209377bd Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 19:51:53 2014 +0200 Removed suggestion of temporary lookup registration from docs commit 21d0c7631c161fc0c67911480be5d3f13f1afa68 Merge: 2509006 f2dc442 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 09:38:23 2014 -0800 Merge pull request #2 from mjtamlyn/lookups_3 Reworked custom lookups docs. commit f2dc4429a1da04c858364972eea57a35a868dab4 Author: Marc Tamlyn <marc.tamlyn@gmail.com> Date: Sun Jan 12 13:15:05 2014 +0000 Reworked custom lookups docs. Mostly just formatting and rewording, but also replaced the example using ``YearExtract`` to use an example which is unlikely to ever be possible directly in the ORM. commit 250900650628d1f11beadb22814abd666029fb81 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Jan 12 13:19:13 2014 +0200 Removed unused import commit 4fba5dfaa022653ffa72497258ffd8f8b7476f92 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 22:34:41 2014 +0200 Added docs to index commit 6d53963f375c77a1f287833b19b976d23f36c30b Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 22:10:24 2014 +0200 Dead code removal commit f9cc0390078e21f1ea5a7bc1f15b09f8f6b0904d Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 19:00:43 2014 +0200 A new try for docs commit 33aa18a6e3c831930bda0028222a26f9c1d96e66 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 14:57:12 2014 +0200 Renamed get_cols to get_group_by_cols commit c7d5f8661b7d364962bed2e6f81161c1b4f1bcc3 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 14:45:53 2014 +0200 Altered query string customization for backends vendors The new way is trying to call first method 'as_' + connection.vendor. If that doesn't exist, then call as_sql(). Also altered how lookup registration is done. There is now RegisterLookupMixin class that is used by Field, Extract and sql.Aggregate. This allows one to register lookups for extracts and aggregates in the same way lookup registration is done for fields. commit 90e7004ec14e15503f828cc9bde2a7dab593814d Merge: 66649ff f7c2c0a Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 13:21:01 2014 +0200 Merge branch 'master' into lookups_3 commit 66649ff891c7c73c7eecf6038c9a6802611b5d8a Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Jan 11 13:16:01 2014 +0200 Some rewording in docs commit 31b8faa62714b4b6b6057a9f5cc106c4dd73caab Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 29 15:52:29 2013 +0200 Cleanup based on review comments commit 1016159f34674c0df871ed891cde72be8340bb5d Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 28 18:37:04 2013 +0200 Proof-of-concept fix for #16731 Implemented only for SQLite and PostgreSQL, and only for startswith and istartswith lookups. commit 193cd097ca8f2cc6a911e57b8e3fb726f96ee6a6 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 28 17:57:58 2013 +0200 Fixed #11722 -- iexact=F() produced invalid SQL commit 08ed3c3b49e100ed9019831e770c25c8f61b70f9 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 23:59:52 2013 +0200 Made Lookup and Extract available from django.db.models commit b99c8d83c972786c6fcd0e84c9e5cb08c1368300 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 23:06:29 2013 +0200 Fixed review notes by Loic commit 049eebc0703c151127f4f0265beceea7b8b39e72 Merge: ed8fab7 b80a835 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 22:53:10 2013 +0200 Merge branch 'master' into lookups_3 Conflicts: django/db/models/fields/__init__.py django/db/models/sql/compiler.py django/db/models/sql/query.py tests/null_queries/tests.py commit ed8fab7fe8867ff3eb801c3697a426478387bb2f Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Dec 21 22:47:23 2013 +0200 Made Extracts aware of full lookup path commit 27a57b7aed91b2f346abc4a77da838bffa17c727 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 21:10:11 2013 +0200 Removed debugger import commit 074e0f5aca0572e368c11e6d2c73c9026e7d63d7 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 21:02:16 2013 +0200 GIS lookup support added commit 760e28e72bae475b442b026650969b0d182dbe53 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 20:04:31 2013 +0200 Removed usage of Constraint, used Lookup instead commit eac47766844b90e7d3269e7a8c012eee34ec0093 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 02:22:30 2013 +0200 Minor cleanup of Lookup API commit 2adf50428d59a783078b0da3d5d035106640c899 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sun Dec 1 02:14:19 2013 +0200 Added documentation, polished implementation commit 32c04357a87e3727a34f8c5e6ec0114d1fbbb303 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Nov 30 23:10:15 2013 +0200 Avoid OrderedDict creation on lookup aggregate check commit 7c8b3a32cc17b4dbca160921d48125f1631e0df4 Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Sat Nov 30 23:04:34 2013 +0200 Implemented nested lookups But there is no support of using lookups outside filtering yet. commit 4d219d4cdef21d9c14e5d6b9299d583d1975fcba Author: Anssi Kääriäinen <akaariai@gmail.com> Date: Wed Nov 27 22:07:30 2013 +0200 Initial implementation of custom lookups
2014-01-18 17:09:43 +08:00
pattern_ops = {
'startswith': "LIKE %s || '%%%%'",
'istartswith': "LIKE UPPER(%s) || '%%%%'",
}
Refactored database exceptions wrapping. Squashed commit of the following: commit 2181d833ed1a2e422494738dcef311164c4e097e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 27 14:28:39 2013 +0100 Fixed #15901 -- Wrapped all PEP-249 exceptions. commit 5476a5d93c19aa2f928c497d39ce6e33f52694e2 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 17:26:52 2013 +0100 Added PEP 3134 exception chaining. Thanks Jacob Kaplan-Moss for the suggestion. commit 9365fad0a650328002fb424457d675a273c95802 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 17:13:49 2013 +0100 Improved API for wrapping database errors. Thanks Alex Gaynor for the proposal. commit 1b463b765f2826f73a8d9266795cd5da4f8d5e9e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 15:00:39 2013 +0100 Removed redundant exception wrapping. This is now taken care of by the cursor wrapper. commit 524bc7345a724bf526bdd2dd1bcf5ede67d6bb5c Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 14:55:10 2013 +0100 Wrapped database exceptions in the base backend. This covers the most common PEP-249 APIs: - Connection APIs: close(), commit(), rollback(), cursor() - Cursor APIs: callproc(), close(), execute(), executemany(), fetchone(), fetchmany(), fetchall(), nextset(). Fixed #19920. commit a66746bb5f0839f35543222787fce3b6a0d0a3ea Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 14:53:34 2013 +0100 Added a wrap_database_exception context manager and decorator. It re-throws backend-specific exceptions using Django's common wrappers.
2013-02-26 21:53:34 +08:00
Database = Database
def __init__(self, *args, **kwargs):
super(DatabaseWrapper, self).__init__(*args, **kwargs)
opts = self.settings_dict["OPTIONS"]
RC = psycopg2.extensions.ISOLATION_LEVEL_READ_COMMITTED
self.isolation_level = opts.get('isolation_level', RC)
self.features = DatabaseFeatures(self)
self.ops = DatabaseOperations(self)
self.client = DatabaseClient(self)
self.creation = DatabaseCreation(self)
self.introspection = DatabaseIntrospection(self)
self.validation = BaseDatabaseValidation(self)
def get_connection_params(self):
settings_dict = self.settings_dict
# None may be used to connect to the default 'postgres' db
if settings_dict['NAME'] == '':
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured(
"settings.DATABASES is improperly configured. "
"Please supply the NAME value.")
conn_params = {
'database': settings_dict['NAME'] or 'postgres',
}
conn_params.update(settings_dict['OPTIONS'])
if 'autocommit' in conn_params:
del conn_params['autocommit']
if 'isolation_level' in conn_params:
del conn_params['isolation_level']
if settings_dict['USER']:
conn_params['user'] = settings_dict['USER']
if settings_dict['PASSWORD']:
conn_params['password'] = force_str(settings_dict['PASSWORD'])
if settings_dict['HOST']:
conn_params['host'] = settings_dict['HOST']
if settings_dict['PORT']:
conn_params['port'] = settings_dict['PORT']
return conn_params
def get_new_connection(self, conn_params):
return Database.connect(**conn_params)
def init_connection_state(self):
settings_dict = self.settings_dict
self.connection.set_client_encoding('UTF8')
tz = 'UTC' if settings.USE_TZ else settings_dict.get('TIME_ZONE')
if tz:
try:
get_parameter_status = self.connection.get_parameter_status
except AttributeError:
# psycopg2 < 2.0.12 doesn't have get_parameter_status
conn_tz = None
else:
conn_tz = get_parameter_status('TimeZone')
if conn_tz != tz:
cursor = self.connection.cursor()
try:
cursor.execute(self.ops.set_time_zone_sql(), [tz])
finally:
cursor.close()
# Commit after setting the time zone (see #17062)
if not self.get_autocommit():
self.connection.commit()
def create_cursor(self):
cursor = self.connection.cursor()
cursor.tzinfo_factory = utc_tzinfo_factory if settings.USE_TZ else None
Refactored database exceptions wrapping. Squashed commit of the following: commit 2181d833ed1a2e422494738dcef311164c4e097e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 27 14:28:39 2013 +0100 Fixed #15901 -- Wrapped all PEP-249 exceptions. commit 5476a5d93c19aa2f928c497d39ce6e33f52694e2 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 17:26:52 2013 +0100 Added PEP 3134 exception chaining. Thanks Jacob Kaplan-Moss for the suggestion. commit 9365fad0a650328002fb424457d675a273c95802 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 17:13:49 2013 +0100 Improved API for wrapping database errors. Thanks Alex Gaynor for the proposal. commit 1b463b765f2826f73a8d9266795cd5da4f8d5e9e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 15:00:39 2013 +0100 Removed redundant exception wrapping. This is now taken care of by the cursor wrapper. commit 524bc7345a724bf526bdd2dd1bcf5ede67d6bb5c Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 14:55:10 2013 +0100 Wrapped database exceptions in the base backend. This covers the most common PEP-249 APIs: - Connection APIs: close(), commit(), rollback(), cursor() - Cursor APIs: callproc(), close(), execute(), executemany(), fetchone(), fetchmany(), fetchall(), nextset(). Fixed #19920. commit a66746bb5f0839f35543222787fce3b6a0d0a3ea Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Tue Feb 26 14:53:34 2013 +0100 Added a wrap_database_exception context manager and decorator. It re-throws backend-specific exceptions using Django's common wrappers.
2013-02-26 21:53:34 +08:00
return cursor
def _set_isolation_level(self, isolation_level):
assert isolation_level in range(1, 5) # Use set_autocommit for level = 0
if self.psycopg2_version >= (2, 4, 2):
self.connection.set_session(isolation_level=isolation_level)
else:
self.connection.set_isolation_level(isolation_level)
def _set_autocommit(self, autocommit):
with self.wrap_database_errors:
if self.psycopg2_version >= (2, 4, 2):
self.connection.autocommit = autocommit
else:
if autocommit:
level = psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT
else:
level = self.isolation_level
self.connection.set_isolation_level(level)
def check_constraints(self, table_names=None):
"""
To check constraints, we set constraints to immediate. Then, when, we're done we must ensure they
are returned to deferred.
"""
self.cursor().execute('SET CONSTRAINTS ALL IMMEDIATE')
self.cursor().execute('SET CONSTRAINTS ALL DEFERRED')
def is_usable(self):
try:
# Use a psycopg cursor directly, bypassing Django's utilities.
self.connection.cursor().execute("SELECT 1")
except Database.Error:
return False
else:
return True
def schema_editor(self, *args, **kwargs):
"Returns a new instance of this backend's SchemaEditor"
return DatabaseSchemaEditor(self, *args, **kwargs)
@cached_property
def psycopg2_version(self):
version = psycopg2.__version__.split(' ', 1)[0]
return tuple(int(v) for v in version.split('.'))
@cached_property
def pg_version(self):
with self.temporary_connection():
return get_version(self.connection)