263 lines
11 KiB
Python
263 lines
11 KiB
Python
from __future__ import unicode_literals
|
|
|
|
from psycopg2.extras import Inet
|
|
|
|
from django.conf import settings
|
|
from django.db.backends.base.operations import BaseDatabaseOperations
|
|
|
|
|
|
class DatabaseOperations(BaseDatabaseOperations):
|
|
def unification_cast_sql(self, output_field):
|
|
internal_type = output_field.get_internal_type()
|
|
if internal_type in ("GenericIPAddressField", "IPAddressField", "TimeField", "UUIDField"):
|
|
# PostgreSQL will resolve a union as type 'text' if input types are
|
|
# 'unknown'.
|
|
# http://www.postgresql.org/docs/9.4/static/typeconv-union-case.html
|
|
# These fields cannot be implicitly cast back in the default
|
|
# PostgreSQL configuration so we need to explicitly cast them.
|
|
# We must also remove components of the type within brackets:
|
|
# varchar(255) -> varchar.
|
|
return 'CAST(%%s AS %s)' % output_field.db_type(self.connection).split('(')[0]
|
|
return '%s'
|
|
|
|
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_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)
|
|
|
|
def _convert_field_to_tz(self, field_name, tzname):
|
|
if settings.USE_TZ:
|
|
field_name = "%s AT TIME ZONE %%s" % field_name
|
|
params = [tzname]
|
|
else:
|
|
params = []
|
|
return field_name, params
|
|
|
|
def datetime_cast_date_sql(self, field_name, tzname):
|
|
field_name, params = self._convert_field_to_tz(field_name, tzname)
|
|
sql = '(%s)::date' % field_name
|
|
return sql, params
|
|
|
|
def datetime_extract_sql(self, lookup_type, field_name, tzname):
|
|
field_name, params = self._convert_field_to_tz(field_name, tzname)
|
|
sql = self.date_extract_sql(lookup_type, field_name)
|
|
return sql, params
|
|
|
|
def datetime_trunc_sql(self, lookup_type, field_name, tzname):
|
|
field_name, params = self._convert_field_to_tz(field_name, tzname)
|
|
# http://www.postgresql.org/docs/current/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
|
|
sql = "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
|
|
return sql, params
|
|
|
|
def deferrable_sql(self):
|
|
return " DEFERRABLE INITIALLY DEFERRED"
|
|
|
|
def fetch_returned_insert_ids(self, cursor):
|
|
"""
|
|
Given a cursor object that has just performed an INSERT...RETURNING
|
|
statement into a table that has an auto-incrementing ID, return the
|
|
list of newly created IDs.
|
|
"""
|
|
return [item[0] for item in cursor.fetchall()]
|
|
|
|
def lookup_cast(self, lookup_type, internal_type=None):
|
|
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'):
|
|
if internal_type in ('IPAddressField', 'GenericIPAddressField'):
|
|
lookup = "HOST(%s)"
|
|
else:
|
|
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 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 prepare_sql_script(self, sql):
|
|
return [sql]
|
|
|
|
def quote_name(self, name):
|
|
if name.startswith('"') and name.endswith('"'):
|
|
return name # Quoting once is enough.
|
|
return '"%s"' % name
|
|
|
|
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.remote_field.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, placeholder_rows):
|
|
placeholder_rows_sql = (", ".join(row) for row in placeholder_rows)
|
|
values_sql = ", ".join("(%s)" % sql for sql in placeholder_rows_sql)
|
|
return "VALUES " + values_sql
|
|
|
|
def adapt_datefield_value(self, value):
|
|
return value
|
|
|
|
def adapt_datetimefield_value(self, value):
|
|
return value
|
|
|
|
def adapt_timefield_value(self, value):
|
|
return value
|
|
|
|
def adapt_ipaddressfield_value(self, value):
|
|
if value:
|
|
return Inet(value)
|
|
return None
|
|
|
|
def subtract_temporals(self, internal_type, lhs, rhs):
|
|
if internal_type == 'DateField':
|
|
lhs_sql, lhs_params = lhs
|
|
rhs_sql, rhs_params = rhs
|
|
return "age(%s, %s)" % (lhs_sql, rhs_sql), lhs_params + rhs_params
|
|
return super(DatabaseOperations, self).subtract_temporals(internal_type, lhs, rhs)
|
|
|
|
def fulltext_search_sql(self, field_name):
|
|
raise NotImplementedError(
|
|
"Add 'django.contrib.postgres' to settings.INSTALLED_APPS to use "
|
|
"the search operator."
|
|
)
|