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

132 lines
5.0 KiB
Python

"""
PostgreSQL database backend for Django.
Requires psycopg 1: http://initd.org/projects/psycopg1
"""
from django.core.db import base, typecasts
import psycopg as Database
DatabaseError = Database.DatabaseError
class DatabaseWrapper:
def __init__(self):
self.connection = None
self.queries = []
def cursor(self):
from django.conf.settings import DATABASE_USER, DATABASE_NAME, DATABASE_HOST, DATABASE_PASSWORD, DEBUG, TIME_ZONE
if self.connection is None:
if DATABASE_NAME == '' or DATABASE_USER == '':
from django.core.exceptions import ImproperlyConfigured
raise ImproperlyConfigured, "You need to specify both DATABASE_NAME and DATABASE_USER in your Django settings file."
conn_string = "user=%s dbname=%s" % (DATABASE_USER, DATABASE_NAME)
if DATABASE_PASSWORD:
conn_string += " password=%s" % DATABASE_PASSWORD
if DATABASE_HOST:
conn_string += " host=%s" % DATABASE_HOST
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", [TIME_ZONE])
if DEBUG:
return base.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
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)
# 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", typecasts.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", typecasts.typecast_time))
Database.register_type(Database.new_type((1114,1184), "TIMESTAMP", typecasts.typecast_timestamp))
Database.register_type(Database.new_type((16,), "BOOLEAN", typecasts.typecast_boolean))
OPERATOR_MAPPING = {
'exact': '=',
'iexact': 'ILIKE',
'contains': 'LIKE',
'icontains': 'ILIKE',
'ne': '!=',
'gt': '>',
'gte': '>=',
'lt': '<',
'lte': '<=',
'startswith': 'LIKE',
'endswith': 'LIKE',
'istartswith': 'ILIKE',
'iendswith': 'ILIKE',
}
# This dictionary maps Field objects to their associated PostgreSQL column
# types, as strings. Column-type strings can contain format strings; they'll
# be interpolated against the values of Field.__dict__ before being output.
# If a column type is set to None, it won't be included in the output.
DATA_TYPES = {
'AutoField': 'serial',
'BooleanField': 'boolean',
'CharField': 'varchar(%(maxlength)s)',
'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)',
'DateField': 'date',
'DateTimeField': 'timestamp with time zone',
'EmailField': 'varchar(75)',
'FileField': 'varchar(100)',
'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)',
'ImageField': 'varchar(100)',
'IntegerField': 'integer',
'IPAddressField': 'inet',
'ManyToManyField': None,
'NullBooleanField': 'boolean',
'OneToOneField': 'integer',
'PhoneNumberField': 'varchar(20)',
'PositiveIntegerField': 'integer CHECK (%(name)s >= 0)',
'PositiveSmallIntegerField': 'smallint CHECK (%(name)s >= 0)',
'SlugField': 'varchar(50)',
'SmallIntegerField': 'smallint',
'TextField': 'text',
'TimeField': 'time',
'URLField': 'varchar(200)',
'USStateField': 'varchar(2)',
'XMLField': 'text',
}