django1/django/core/db/backends/sqlite3.py

182 lines
6.3 KiB
Python

"""
SQLite3 backend for django. Requires pysqlite2 (http://pysqlite.org/).
"""
from django.core.db import base, typecasts
from django.core.db.dicthelpers import *
from pysqlite2 import dbapi2 as Database
DatabaseError = Database.DatabaseError
# Register adaptors ###########################################################
Database.register_converter("bool", lambda s: str(s) == '1')
Database.register_converter("time", typecasts.typecast_time)
Database.register_converter("date", typecasts.typecast_date)
Database.register_converter("datetime", typecasts.typecast_timestamp)
# Database wrapper ############################################################
def utf8rowFactory(cursor, row):
def utf8(s):
if type(s) == unicode:
return s.encode("utf-8")
else:
return s
return [utf8(r) for r in row]
class DatabaseWrapper:
def __init__(self):
self.connection = None
self.queries = []
def cursor(self):
from django.conf.settings import DATABASE_NAME, DEBUG
if self.connection is None:
self.connection = Database.connect(DATABASE_NAME, detect_types=Database.PARSE_DECLTYPES)
# register extract and date_trun functions
self.connection.create_function("django_extract", 2, _sqlite_extract)
self.connection.create_function("django_date_trunc", 2, _sqlite_date_trunc)
cursor = self.connection.cursor(factory=SQLiteCursorWrapper)
cursor.row_factory = utf8rowFactory
if DEBUG:
return base.CursorDebugWrapper(cursor, self)
else:
return cursor
def commit(self):
self.connection.commit()
def rollback(self):
if self.connection:
self.connection.rollback()
def close(self):
if self.connection is not None:
self.connection.close()
self.connection = None
class SQLiteCursorWrapper(Database.Cursor):
"""
Django uses "format" style placeholders, but pysqlite2 uses "qmark" style.
This fixes it -- but note that if you want to use a literal "%s" in a query,
you'll need to use "%%s" (which I belive is true of other wrappers as well).
"""
def execute(self, query, params=[]):
query = self.convert_query(query, len(params))
return Database.Cursor.execute(self, query, params)
def executemany(self, query, params=[]):
query = self.convert_query(query, len(params[0]))
return Database.Cursor.executemany(self, query, params)
def convert_query(self, query, num_params):
# XXX this seems too simple to be correct... is this right?
return query % tuple("?" * num_params)
# Helper functions ############################################################
def get_last_insert_id(cursor, table_name, pk_name):
return cursor.lastrowid
def get_date_extract_sql(lookup_type, table_name):
# lookup_type is 'year', 'month', 'day'
# sqlite doesn't support extract, so we fake it with the user-defined
# function _sqlite_extract that's registered in connect(), above.
return 'django_extract("%s", %s)' % (lookup_type.lower(), table_name)
def _sqlite_extract(lookup_type, dt):
try:
dt = typecasts.typecast_timestamp(dt)
except (ValueError, TypeError):
return None
return str(getattr(dt, lookup_type))
def get_date_trunc_sql(lookup_type, field_name):
# lookup_type is 'year', 'month', 'day'
# sqlite doesn't support DATE_TRUNC, so we fake it as above.
return 'django_date_trunc("%s", %s)' % (lookup_type.lower(), 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 _sqlite_date_trunc(lookup_type, dt):
try:
dt = typecasts.typecast_timestamp(dt)
except (ValueError, TypeError):
return None
if lookup_type == 'year':
return "%i-01-01 00:00:00" % dt.year
elif lookup_type == 'month':
return "%i-%02i-01 00:00:00" % (dt.year, dt.month)
elif lookup_type == 'day':
return "%i-%02i-%02i 00:00:00" % (dt.year, dt.month, dt.day)
def get_table_list(cursor):
raise NotImplementedError
def get_relations(cursor, table_name):
raise NotImplementedError
def quote_name(name):
if name.startswith('"') and name.endswith('"'):
return name # Quoting once is enough.
return '"%s"' % name
# Operators and fields ########################################################
OPERATOR_MAPPING = {
'exact': '=',
'iexact': 'LIKE',
'contains': 'LIKE',
'icontains': 'LIKE',
'ne': '!=',
'gt': '>',
'gte': '>=',
'lt': '<',
'lte': '<=',
'startswith': 'LIKE',
'endswith': 'LIKE',
'istartswith': 'LIKE',
'iendswith': 'LIKE',
}
# SQLite doesn't actually support most of these types, but it "does the right
# thing" given more verbose field definitions, so leave them as is so that
# schema inspection is more useful.
DATA_TYPES = {
'AutoField': 'integer',
'BooleanField': 'bool',
'CharField': 'varchar(%(maxlength)s)',
'CommaSeparatedIntegerField': 'varchar(%(maxlength)s)',
'DateField': 'date',
'DateTimeField': 'datetime',
'EmailField': 'varchar(75)',
'FileField': 'varchar(100)',
'FilePathField': 'varchar(100)',
'FloatField': 'numeric(%(max_digits)s, %(decimal_places)s)',
'ImageField': 'varchar(100)',
'IntegerField': 'integer',
'IPAddressField': 'char(15)',
'ManyToManyField': None,
'NullBooleanField': 'bool',
'OneToOneField': 'integer',
'PhoneNumberField': 'varchar(20)',
'PositiveIntegerField': 'integer unsigned',
'PositiveSmallIntegerField': 'smallint unsigned',
'SlugField': 'varchar(50)',
'SmallIntegerField': 'smallint',
'TextField': 'text',
'TimeField': 'time',
'URLField': 'varchar(200)',
'USStateField': 'varchar(2)',
}
DATA_TYPES_REVERSE = {}