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

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from __future__ import unicode_literals
Fixed #17260 -- Added time zone aware aggregation and lookups. Thanks Carl Meyer for the review. Squashed commit of the following: commit 4f290bdb60b7d8534abf4ca901bd0844612dcbda Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 21:21:30 2013 +0100 Used '0:00' instead of 'UTC' which doesn't always exist in Oracle. Thanks Ian Kelly for the suggestion. commit 01b6366f3ce67d57a58ca8f25e5be77911748638 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 13:38:43 2013 +0100 Made tzname a parameter of datetime_extract/trunc_sql. This is required to work around a bug in Oracle. commit 924a144ef8a80ba4daeeafbe9efaa826566e9d02 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 14:47:44 2013 +0100 Added support for parameters in SELECT clauses. commit b4351d2890cd1090d3ff2d203fe148937324c935 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 22:30:22 2013 +0100 Documented backwards incompatibilities in the two previous commits. commit 91ef84713c81bd455f559dacf790e586d08cacb9 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:42:31 2013 +0100 Used QuerySet.datetimes for the admin's date_hierarchy. commit 0d0de288a5210fa106cd4350961eb2006535cc5c Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:29:38 2013 +0100 Used QuerySet.datetimes in date-based generic views. commit 9c0859ff7c0b00734afe7fc15609d43d83215072 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:25 2013 +0100 Implemented QuerySet.datetimes on Oracle. commit 68ab511a4ffbd2b811bf5da174d47e4dd90f28fc Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:14 2013 +0100 Implemented QuerySet.datetimes on MySQL. commit 22d52681d347a8cdf568dc31ed032cbc61d049ef Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:42:29 2013 +0100 Implemented QuerySet.datetimes on SQLite. commit f6800fd04c93722b45f9236976389e0b2fe436f5 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:03 2013 +0100 Implemented QuerySet.datetimes on PostgreSQL. commit 0c829c23f4cf4d6804cadcc93032dd4c26b8c65e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:41:08 2013 +0100 Added datetime-handling infrastructure in the ORM layers. commit 104d82a7778cf3f0f5d03dfa53709c26df45daad Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 10:05:55 2013 +0100 Updated null_queries tests to avoid clashing with the __second lookup. commit c01bbb32358201b3ac8cb4291ef87b7612a2b8e6 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 23:07:41 2013 +0100 Updated tests of .dates(). Replaced .dates() by .datetimes() for DateTimeFields. Replaced dates with datetimes in the expected output for DateFields. commit 50fb7a52462fecf0127b38e7f3df322aeb287c43 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:40:09 2013 +0100 Updated and added tests for QuerySet.datetimes. commit a8451a5004c437190e264667b1e6fb8acc3c1eeb Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 22:34:46 2013 +0100 Documented the new time lookups and updated the date lookups. commit 29413eab2bd1d5e004598900c0dadc0521bbf4d3 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 16:15:49 2013 +0100 Documented QuerySet.datetimes and updated QuerySet.dates.
2013-02-10 23:15:49 +08:00
from django.conf import settings
from django.db.backends import BaseDatabaseOperations
class DatabaseOperations(BaseDatabaseOperations):
def __init__(self, connection):
super(DatabaseOperations, self).__init__(connection)
def date_extract_sql(self, lookup_type, field_name):
# http://www.postgresql.org/docs/current/static/functions-datetime.html#FUNCTIONS-DATETIME-EXTRACT
if lookup_type == 'week_day':
# For consistency across backends, we return Sunday=1, Saturday=7.
return "EXTRACT('dow' FROM %s) + 1" % field_name
else:
return "EXTRACT('%s' FROM %s)" % (lookup_type, field_name)
def date_interval_sql(self, sql, connector, timedelta):
"""
implements the interval functionality for expressions
format for Postgres:
(datefield + interval '3 days 200 seconds 5 microseconds')
"""
modifiers = []
if timedelta.days:
modifiers.append('%s days' % timedelta.days)
if timedelta.seconds:
modifiers.append('%s seconds' % timedelta.seconds)
if timedelta.microseconds:
modifiers.append('%s microseconds' % timedelta.microseconds)
mods = ' '.join(modifiers)
conn = ' %s ' % connector
return '(%s)' % conn.join([sql, 'interval \'%s\'' % mods])
def date_trunc_sql(self, lookup_type, field_name):
# http://www.postgresql.org/docs/current/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
Fixed #17260 -- Added time zone aware aggregation and lookups. Thanks Carl Meyer for the review. Squashed commit of the following: commit 4f290bdb60b7d8534abf4ca901bd0844612dcbda Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 21:21:30 2013 +0100 Used '0:00' instead of 'UTC' which doesn't always exist in Oracle. Thanks Ian Kelly for the suggestion. commit 01b6366f3ce67d57a58ca8f25e5be77911748638 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 13:38:43 2013 +0100 Made tzname a parameter of datetime_extract/trunc_sql. This is required to work around a bug in Oracle. commit 924a144ef8a80ba4daeeafbe9efaa826566e9d02 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 14:47:44 2013 +0100 Added support for parameters in SELECT clauses. commit b4351d2890cd1090d3ff2d203fe148937324c935 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 22:30:22 2013 +0100 Documented backwards incompatibilities in the two previous commits. commit 91ef84713c81bd455f559dacf790e586d08cacb9 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:42:31 2013 +0100 Used QuerySet.datetimes for the admin's date_hierarchy. commit 0d0de288a5210fa106cd4350961eb2006535cc5c Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:29:38 2013 +0100 Used QuerySet.datetimes in date-based generic views. commit 9c0859ff7c0b00734afe7fc15609d43d83215072 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:25 2013 +0100 Implemented QuerySet.datetimes on Oracle. commit 68ab511a4ffbd2b811bf5da174d47e4dd90f28fc Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:14 2013 +0100 Implemented QuerySet.datetimes on MySQL. commit 22d52681d347a8cdf568dc31ed032cbc61d049ef Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:42:29 2013 +0100 Implemented QuerySet.datetimes on SQLite. commit f6800fd04c93722b45f9236976389e0b2fe436f5 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:03 2013 +0100 Implemented QuerySet.datetimes on PostgreSQL. commit 0c829c23f4cf4d6804cadcc93032dd4c26b8c65e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:41:08 2013 +0100 Added datetime-handling infrastructure in the ORM layers. commit 104d82a7778cf3f0f5d03dfa53709c26df45daad Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 10:05:55 2013 +0100 Updated null_queries tests to avoid clashing with the __second lookup. commit c01bbb32358201b3ac8cb4291ef87b7612a2b8e6 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 23:07:41 2013 +0100 Updated tests of .dates(). Replaced .dates() by .datetimes() for DateTimeFields. Replaced dates with datetimes in the expected output for DateFields. commit 50fb7a52462fecf0127b38e7f3df322aeb287c43 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:40:09 2013 +0100 Updated and added tests for QuerySet.datetimes. commit a8451a5004c437190e264667b1e6fb8acc3c1eeb Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 22:34:46 2013 +0100 Documented the new time lookups and updated the date lookups. commit 29413eab2bd1d5e004598900c0dadc0521bbf4d3 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 16:15:49 2013 +0100 Documented QuerySet.datetimes and updated QuerySet.dates.
2013-02-10 23:15:49 +08:00
def datetime_extract_sql(self, lookup_type, field_name, tzname):
if settings.USE_TZ:
field_name = "%s AT TIME ZONE %%s" % field_name
params = [tzname]
else:
params = []
# http://www.postgresql.org/docs/current/static/functions-datetime.html#FUNCTIONS-DATETIME-EXTRACT
Fixed #17260 -- Added time zone aware aggregation and lookups. Thanks Carl Meyer for the review. Squashed commit of the following: commit 4f290bdb60b7d8534abf4ca901bd0844612dcbda Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 21:21:30 2013 +0100 Used '0:00' instead of 'UTC' which doesn't always exist in Oracle. Thanks Ian Kelly for the suggestion. commit 01b6366f3ce67d57a58ca8f25e5be77911748638 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 13:38:43 2013 +0100 Made tzname a parameter of datetime_extract/trunc_sql. This is required to work around a bug in Oracle. commit 924a144ef8a80ba4daeeafbe9efaa826566e9d02 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 14:47:44 2013 +0100 Added support for parameters in SELECT clauses. commit b4351d2890cd1090d3ff2d203fe148937324c935 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 22:30:22 2013 +0100 Documented backwards incompatibilities in the two previous commits. commit 91ef84713c81bd455f559dacf790e586d08cacb9 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:42:31 2013 +0100 Used QuerySet.datetimes for the admin's date_hierarchy. commit 0d0de288a5210fa106cd4350961eb2006535cc5c Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:29:38 2013 +0100 Used QuerySet.datetimes in date-based generic views. commit 9c0859ff7c0b00734afe7fc15609d43d83215072 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:25 2013 +0100 Implemented QuerySet.datetimes on Oracle. commit 68ab511a4ffbd2b811bf5da174d47e4dd90f28fc Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:14 2013 +0100 Implemented QuerySet.datetimes on MySQL. commit 22d52681d347a8cdf568dc31ed032cbc61d049ef Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:42:29 2013 +0100 Implemented QuerySet.datetimes on SQLite. commit f6800fd04c93722b45f9236976389e0b2fe436f5 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:03 2013 +0100 Implemented QuerySet.datetimes on PostgreSQL. commit 0c829c23f4cf4d6804cadcc93032dd4c26b8c65e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:41:08 2013 +0100 Added datetime-handling infrastructure in the ORM layers. commit 104d82a7778cf3f0f5d03dfa53709c26df45daad Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 10:05:55 2013 +0100 Updated null_queries tests to avoid clashing with the __second lookup. commit c01bbb32358201b3ac8cb4291ef87b7612a2b8e6 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 23:07:41 2013 +0100 Updated tests of .dates(). Replaced .dates() by .datetimes() for DateTimeFields. Replaced dates with datetimes in the expected output for DateFields. commit 50fb7a52462fecf0127b38e7f3df322aeb287c43 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:40:09 2013 +0100 Updated and added tests for QuerySet.datetimes. commit a8451a5004c437190e264667b1e6fb8acc3c1eeb Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 22:34:46 2013 +0100 Documented the new time lookups and updated the date lookups. commit 29413eab2bd1d5e004598900c0dadc0521bbf4d3 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 16:15:49 2013 +0100 Documented QuerySet.datetimes and updated QuerySet.dates.
2013-02-10 23:15:49 +08:00
if lookup_type == 'week_day':
# For consistency across backends, we return Sunday=1, Saturday=7.
sql = "EXTRACT('dow' FROM %s) + 1" % field_name
else:
sql = "EXTRACT('%s' FROM %s)" % (lookup_type, field_name)
return sql, params
def datetime_trunc_sql(self, lookup_type, field_name, tzname):
if settings.USE_TZ:
field_name = "%s AT TIME ZONE %%s" % field_name
params = [tzname]
else:
params = []
# http://www.postgresql.org/docs/current/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
Fixed #17260 -- Added time zone aware aggregation and lookups. Thanks Carl Meyer for the review. Squashed commit of the following: commit 4f290bdb60b7d8534abf4ca901bd0844612dcbda Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 21:21:30 2013 +0100 Used '0:00' instead of 'UTC' which doesn't always exist in Oracle. Thanks Ian Kelly for the suggestion. commit 01b6366f3ce67d57a58ca8f25e5be77911748638 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 13:38:43 2013 +0100 Made tzname a parameter of datetime_extract/trunc_sql. This is required to work around a bug in Oracle. commit 924a144ef8a80ba4daeeafbe9efaa826566e9d02 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Wed Feb 13 14:47:44 2013 +0100 Added support for parameters in SELECT clauses. commit b4351d2890cd1090d3ff2d203fe148937324c935 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 22:30:22 2013 +0100 Documented backwards incompatibilities in the two previous commits. commit 91ef84713c81bd455f559dacf790e586d08cacb9 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:42:31 2013 +0100 Used QuerySet.datetimes for the admin's date_hierarchy. commit 0d0de288a5210fa106cd4350961eb2006535cc5c Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 09:29:38 2013 +0100 Used QuerySet.datetimes in date-based generic views. commit 9c0859ff7c0b00734afe7fc15609d43d83215072 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:25 2013 +0100 Implemented QuerySet.datetimes on Oracle. commit 68ab511a4ffbd2b811bf5da174d47e4dd90f28fc Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:14 2013 +0100 Implemented QuerySet.datetimes on MySQL. commit 22d52681d347a8cdf568dc31ed032cbc61d049ef Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:42:29 2013 +0100 Implemented QuerySet.datetimes on SQLite. commit f6800fd04c93722b45f9236976389e0b2fe436f5 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:43:03 2013 +0100 Implemented QuerySet.datetimes on PostgreSQL. commit 0c829c23f4cf4d6804cadcc93032dd4c26b8c65e Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:41:08 2013 +0100 Added datetime-handling infrastructure in the ORM layers. commit 104d82a7778cf3f0f5d03dfa53709c26df45daad Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Mon Feb 11 10:05:55 2013 +0100 Updated null_queries tests to avoid clashing with the __second lookup. commit c01bbb32358201b3ac8cb4291ef87b7612a2b8e6 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 23:07:41 2013 +0100 Updated tests of .dates(). Replaced .dates() by .datetimes() for DateTimeFields. Replaced dates with datetimes in the expected output for DateFields. commit 50fb7a52462fecf0127b38e7f3df322aeb287c43 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 21:40:09 2013 +0100 Updated and added tests for QuerySet.datetimes. commit a8451a5004c437190e264667b1e6fb8acc3c1eeb Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 22:34:46 2013 +0100 Documented the new time lookups and updated the date lookups. commit 29413eab2bd1d5e004598900c0dadc0521bbf4d3 Author: Aymeric Augustin <aymeric.augustin@m4x.org> Date: Sun Feb 10 16:15:49 2013 +0100 Documented QuerySet.datetimes and updated QuerySet.dates.
2013-02-10 23:15:49 +08:00
sql = "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
return sql, params
def deferrable_sql(self):
return " DEFERRABLE INITIALLY DEFERRED"
def lookup_cast(self, lookup_type):
lookup = '%s'
# Cast text lookups to text to allow things like filter(x__contains=4)
if lookup_type in ('iexact', 'contains', 'icontains', 'startswith',
'istartswith', 'endswith', 'iendswith', 'regex', 'iregex'):
lookup = "%s::text"
# Use UPPER(x) for case-insensitive lookups; it's faster.
if lookup_type in ('iexact', 'icontains', 'istartswith', 'iendswith'):
lookup = 'UPPER(%s)' % lookup
return lookup
def field_cast_sql(self, db_type, internal_type):
if internal_type == "GenericIPAddressField" or internal_type == "IPAddressField":
return 'HOST(%s)'
return '%s'
def last_insert_id(self, cursor, table_name, pk_name):
# Use pg_get_serial_sequence to get the underlying sequence name
# from the table name and column name (available since PostgreSQL 8)
cursor.execute("SELECT CURRVAL(pg_get_serial_sequence('%s','%s'))" % (
self.quote_name(table_name), pk_name))
return cursor.fetchone()[0]
def no_limit_value(self):
return None
def quote_name(self, name):
if name.startswith('"') and name.endswith('"'):
return name # Quoting once is enough.
return '"%s"' % name
def quote_parameter(self, value):
# Inner import so backend fails nicely if it's not present
import psycopg2
return psycopg2.extensions.adapt(value)
def set_time_zone_sql(self):
return "SET TIME ZONE %s"
def sql_flush(self, style, tables, sequences, allow_cascade=False):
if tables:
# Perform a single SQL 'TRUNCATE x, y, z...;' statement. It allows
# us to truncate tables referenced by a foreign key in any other
# table.
tables_sql = ', '.join(
style.SQL_FIELD(self.quote_name(table)) for table in tables)
if allow_cascade:
sql = ['%s %s %s;' % (
style.SQL_KEYWORD('TRUNCATE'),
tables_sql,
style.SQL_KEYWORD('CASCADE'),
)]
else:
sql = ['%s %s;' % (
style.SQL_KEYWORD('TRUNCATE'),
tables_sql,
)]
sql.extend(self.sequence_reset_by_name_sql(style, sequences))
return sql
else:
return []
def sequence_reset_by_name_sql(self, style, sequences):
# 'ALTER SEQUENCE sequence_name RESTART WITH 1;'... style SQL statements
# to reset sequence indices
sql = []
for sequence_info in sequences:
table_name = sequence_info['table']
column_name = sequence_info['column']
if not (column_name and len(column_name) > 0):
# This will be the case if it's an m2m using an autogenerated
# intermediate table (see BaseDatabaseIntrospection.sequence_list)
column_name = 'id'
sql.append("%s setval(pg_get_serial_sequence('%s','%s'), 1, false);" %
(style.SQL_KEYWORD('SELECT'),
style.SQL_TABLE(self.quote_name(table_name)),
style.SQL_FIELD(column_name))
)
return sql
def tablespace_sql(self, tablespace, inline=False):
if inline:
return "USING INDEX TABLESPACE %s" % self.quote_name(tablespace)
else:
return "TABLESPACE %s" % self.quote_name(tablespace)
def sequence_reset_sql(self, style, model_list):
from django.db import models
output = []
qn = self.quote_name
for model in model_list:
# Use `coalesce` to set the sequence for each model to the max pk value if there are records,
# or 1 if there are none. Set the `is_called` property (the third argument to `setval`) to true
# if there are records (as the max pk value is already in use), otherwise set it to false.
# Use pg_get_serial_sequence to get the underlying sequence name from the table name
# and column name (available since PostgreSQL 8)
for f in model._meta.local_fields:
if isinstance(f, models.AutoField):
output.append("%s setval(pg_get_serial_sequence('%s','%s'), coalesce(max(%s), 1), max(%s) %s null) %s %s;" %
(style.SQL_KEYWORD('SELECT'),
style.SQL_TABLE(qn(model._meta.db_table)),
style.SQL_FIELD(f.column),
style.SQL_FIELD(qn(f.column)),
style.SQL_FIELD(qn(f.column)),
style.SQL_KEYWORD('IS NOT'),
style.SQL_KEYWORD('FROM'),
style.SQL_TABLE(qn(model._meta.db_table))))
break # Only one AutoField is allowed per model, so don't bother continuing.
for f in model._meta.many_to_many:
if not f.rel.through:
output.append("%s setval(pg_get_serial_sequence('%s','%s'), coalesce(max(%s), 1), max(%s) %s null) %s %s;" %
(style.SQL_KEYWORD('SELECT'),
style.SQL_TABLE(qn(f.m2m_db_table())),
style.SQL_FIELD('id'),
style.SQL_FIELD(qn('id')),
style.SQL_FIELD(qn('id')),
style.SQL_KEYWORD('IS NOT'),
style.SQL_KEYWORD('FROM'),
style.SQL_TABLE(qn(f.m2m_db_table()))))
return output
def prep_for_iexact_query(self, x):
return x
def max_name_length(self):
"""
Returns the maximum length of an identifier.
Note that the maximum length of an identifier is 63 by default, but can
be changed by recompiling PostgreSQL after editing the NAMEDATALEN
macro in src/include/pg_config_manual.h .
This implementation simply returns 63, but can easily be overridden by a
custom database backend that inherits most of its behavior from this one.
"""
return 63
def distinct_sql(self, fields):
if fields:
return 'DISTINCT ON (%s)' % ', '.join(fields)
else:
return 'DISTINCT'
def last_executed_query(self, cursor, sql, params):
# http://initd.org/psycopg/docs/cursor.html#cursor.query
# The query attribute is a Psycopg extension to the DB API 2.0.
if cursor.query is not None:
return cursor.query.decode('utf-8')
return None
def return_insert_id(self):
return "RETURNING %s", ()
def bulk_insert_sql(self, fields, num_values):
items_sql = "(%s)" % ", ".join(["%s"] * len(fields))
return "VALUES " + ", ".join([items_sql] * num_values)