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

139 lines
4.7 KiB
Python

"""
PostgreSQL database backend for Django.
Requires psycopg 1: http://initd.org/projects/psycopg1
"""
from django.db.backends import util
try:
import psycopg as Database
except ImportError, e:
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured, "Error loading psycopg module: %s" % e
DatabaseError = Database.DatabaseError
try:
# Only exists in Python 2.4+
from threading import local
except ImportError:
# Import copy of _thread_local.py from Python 2.4
from django.utils._threading_local import local
class DatabaseWrapper(local):
def __init__(self):
self.connection = None
self.queries = []
def cursor(self):
from django.conf import settings
if self.connection is None:
if settings.DATABASE_NAME == '':
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured, "You need to specify DATABASE_NAME in your Django settings file."
conn_string = "dbname=%s" % settings.DATABASE_NAME
if settings.DATABASE_USER:
conn_string = "user=%s %s" % (settings.DATABASE_USER, conn_string)
if settings.DATABASE_PASSWORD:
conn_string += " password='%s'" % settings.DATABASE_PASSWORD
if settings.DATABASE_HOST:
conn_string += " host=%s" % settings.DATABASE_HOST
if settings.DATABASE_PORT:
conn_string += " port=%s" % settings.DATABASE_PORT
self.connection = Database.connect(conn_string)
self.connection.set_isolation_level(1) # make transactions transparent to all cursors
cursor = self.connection.cursor()
cursor.execute("SET TIME ZONE %s", [settings.TIME_ZONE])
if settings.DEBUG:
return util.CursorDebugWrapper(cursor, self)
return cursor
def _commit(self):
return self.connection.commit()
def _rollback(self):
if self.connection:
return self.connection.rollback()
def close(self):
if self.connection is not None:
self.connection.close()
self.connection = None
supports_constraints = True
def quote_name(name):
if name.startswith('"') and name.endswith('"'):
return name # Quoting once is enough.
return '"%s"' % name
def dictfetchone(cursor):
"Returns a row from the cursor as a dict"
return cursor.dictfetchone()
def dictfetchmany(cursor, number):
"Returns a certain number of rows from a cursor as a dict"
return cursor.dictfetchmany(number)
def dictfetchall(cursor):
"Returns all rows from a cursor as a dict"
return cursor.dictfetchall()
def get_last_insert_id(cursor, table_name, pk_name):
cursor.execute("SELECT CURRVAL('\"%s_%s_seq\"')" % (table_name, pk_name))
return cursor.fetchone()[0]
def get_date_extract_sql(lookup_type, table_name):
# lookup_type is 'year', 'month', 'day'
# http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-EXTRACT
return "EXTRACT('%s' FROM %s)" % (lookup_type, table_name)
def get_date_trunc_sql(lookup_type, field_name):
# lookup_type is 'year', 'month', 'day'
# http://www.postgresql.org/docs/8.0/static/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
def get_limit_offset_sql(limit, offset=None):
sql = "LIMIT %s" % limit
if offset and offset != 0:
sql += " OFFSET %s" % offset
return sql
def get_random_function_sql():
return "RANDOM()"
def get_fulltext_search_sql(field_name):
raise NotImplementedError
def get_drop_foreignkey_sql():
return "DROP CONSTRAINT"
def get_pk_default_value():
return "DEFAULT"
# Register these custom typecasts, because Django expects dates/times to be
# in Python's native (standard-library) datetime/time format, whereas psycopg
# use mx.DateTime by default.
try:
Database.register_type(Database.new_type((1082,), "DATE", util.typecast_date))
except AttributeError:
raise Exception, "You appear to be using psycopg version 2, which isn't supported yet, because it's still in beta. Use psycopg version 1 instead: http://initd.org/projects/psycopg1"
Database.register_type(Database.new_type((1083,1266), "TIME", util.typecast_time))
Database.register_type(Database.new_type((1114,1184), "TIMESTAMP", util.typecast_timestamp))
Database.register_type(Database.new_type((16,), "BOOLEAN", util.typecast_boolean))
OPERATOR_MAPPING = {
'exact': '= %s',
'iexact': 'ILIKE %s',
'contains': 'LIKE %s',
'icontains': 'ILIKE %s',
'gt': '> %s',
'gte': '>= %s',
'lt': '< %s',
'lte': '<= %s',
'startswith': 'LIKE %s',
'endswith': 'LIKE %s',
'istartswith': 'ILIKE %s',
'iendswith': 'ILIKE %s',
}