webapp/django/db/backends/sqlite3/base.py - gerrit - Git at Google

 """
 SQLite3 backend for django.

 Python 2.3 and 2.4 require pysqlite2 (http://pysqlite.org/).

 Python 2.5 and later use the sqlite3 module in the standard library.
 """

 from django.db.backends import *
 from django.db.backends.sqlite3.client import DatabaseClient
 from django.db.backends.sqlite3.creation import DatabaseCreation
 from django.db.backends.sqlite3.introspection import DatabaseIntrospection

 try:
     try:
         from sqlite3 import dbapi2 as Database
     except ImportError:
         from pysqlite2 import dbapi2 as Database
 except ImportError, e:
     import sys
     from django.core.exceptions import ImproperlyConfigured
     if sys.version_info < (2, 5, 0):
         module = 'pysqlite2'
     else:
         module = 'sqlite3'
     raise ImproperlyConfigured, "Error loading %s module: %s" % (module, e)

 try:
     import decimal
 except ImportError:
     from django.utils import _decimal as decimal # for Python 2.3

 DatabaseError = Database.DatabaseError
 IntegrityError = Database.IntegrityError

 Database.register_converter("bool", lambda s: str(s) == '1')
 Database.register_converter("time", util.typecast_time)
 Database.register_converter("date", util.typecast_date)
 Database.register_converter("datetime", util.typecast_timestamp)
 Database.register_converter("timestamp", util.typecast_timestamp)
 Database.register_converter("TIMESTAMP", util.typecast_timestamp)
 Database.register_converter("decimal", util.typecast_decimal)
 Database.register_adapter(decimal.Decimal, util.rev_typecast_decimal)
 if Database.version_info >= (2,4,1):
     # Starting in 2.4.1, the str type is not accepted anymore, therefore,
     # we convert all str objects to Unicode
     # As registering a adapter for a primitive type causes a small
     # slow-down, this adapter is only registered for sqlite3 versions
     # needing it.
     Database.register_adapter(str, lambda s:s.decode('utf-8'))

 class DatabaseFeatures(BaseDatabaseFeatures):
     # SQLite cannot handle us only partially reading from a cursor's result set
     # and then writing the same rows to the database in another cursor. This
     # setting ensures we always read result sets fully into memory all in one
     # go.
     can_use_chunked_reads = False

 class DatabaseOperations(BaseDatabaseOperations):
     def date_extract_sql(self, lookup_type, field_name):
         # sqlite doesn't support extract, so we fake it with the user-defined
         # function django_extract that's registered in connect().
         return 'django_extract("%s", %s)' % (lookup_type.lower(), field_name)

     def date_trunc_sql(self, lookup_type, field_name):
         # sqlite doesn't support DATE_TRUNC, so we fake it with a user-defined
         # function django_date_trunc that's registered in connect().
         return 'django_date_trunc("%s", %s)' % (lookup_type.lower(), field_name)

     def drop_foreignkey_sql(self):
         return ""

     def pk_default_value(self):
         return 'NULL'

     def quote_name(self, name):
         if name.startswith('"') and name.endswith('"'):
             return name # Quoting once is enough.
         return '"%s"' % name

     def no_limit_value(self):
         return -1

     def sql_flush(self, style, tables, sequences):
         # NB: The generated SQL below is specific to SQLite
         # Note: The DELETE FROM... SQL generated below works for SQLite databases
         # because constraints don't exist
         sql = ['%s %s %s;' % \
                 (style.SQL_KEYWORD('DELETE'),
                  style.SQL_KEYWORD('FROM'),
                  style.SQL_FIELD(self.quote_name(table))
                  ) for table in tables]
         # Note: No requirement for reset of auto-incremented indices (cf. other
         # sql_flush() implementations). Just return SQL at this point
         return sql

     def year_lookup_bounds(self, value):
         first = '%s-01-01'
         second = '%s-12-31 23:59:59.999999'
         return [first % value, second % value]

 class DatabaseWrapper(BaseDatabaseWrapper):

     # SQLite requires LIKE statements to include an ESCAPE clause if the value
     # being escaped has a percent or underscore in it.
     # See http://www.sqlite.org/lang_expr.html for an explanation.
     operators = {
         'exact': '= %s',
         'iexact': "LIKE %s ESCAPE '\\'",
         'contains': "LIKE %s ESCAPE '\\'",
         'icontains': "LIKE %s ESCAPE '\\'",
         'regex': 'REGEXP %s',
         'iregex': "REGEXP '(?i)' || %s",
         'gt': '> %s',
         'gte': '>= %s',
         'lt': '< %s',
         'lte': '<= %s',
         'startswith': "LIKE %s ESCAPE '\\'",
         'endswith': "LIKE %s ESCAPE '\\'",
         'istartswith': "LIKE %s ESCAPE '\\'",
         'iendswith': "LIKE %s ESCAPE '\\'",
     }

     def __init__(self, *args, **kwargs):
         super(DatabaseWrapper, self).__init__(*args, **kwargs)

         self.features = DatabaseFeatures()
         self.ops = DatabaseOperations()
         self.client = DatabaseClient()
         self.creation = DatabaseCreation(self)
         self.introspection = DatabaseIntrospection(self)
         self.validation = BaseDatabaseValidation()

     def _cursor(self, settings):
         if self.connection is None:
             if not settings.DATABASE_NAME:
                 from django.core.exceptions import ImproperlyConfigured
                 raise ImproperlyConfigured, "Please fill out DATABASE_NAME in the settings module before using the database."
             kwargs = {
                 'database': settings.DATABASE_NAME,
                 'detect_types': Database.PARSE_DECLTYPES | Database.PARSE_COLNAMES,
             }
             kwargs.update(self.options)
             self.connection = Database.connect(**kwargs)
             # Register extract, date_trunc, and regexp functions.
             self.connection.create_function("django_extract", 2, _sqlite_extract)
             self.connection.create_function("django_date_trunc", 2, _sqlite_date_trunc)
             self.connection.create_function("regexp", 2, _sqlite_regexp)
         return self.connection.cursor(factory=SQLiteCursorWrapper)

     def close(self):
         from django.conf import settings
         # If database is in memory, closing the connection destroys the
         # database. To prevent accidental data loss, ignore close requests on
         # an in-memory db.
         if settings.DATABASE_NAME != ":memory:":
             BaseDatabaseWrapper.close(self)

 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".
     """
     def execute(self, query, params=()):
         query = self.convert_query(query, len(params))
         return Database.Cursor.execute(self, query, params)

     def executemany(self, query, param_list):
         try:
           query = self.convert_query(query, len(param_list[0]))
           return Database.Cursor.executemany(self, query, param_list)
         except (IndexError,TypeError):
           # No parameter list provided
           return None

     def convert_query(self, query, num_params):
         return query % tuple("?" * num_params)

 def _sqlite_extract(lookup_type, dt):
     try:
         dt = util.typecast_timestamp(dt)
     except (ValueError, TypeError):
         return None
     return unicode(getattr(dt, lookup_type))

 def _sqlite_date_trunc(lookup_type, dt):
     try:
         dt = util.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 _sqlite_regexp(re_pattern, re_string):
     import re
     try:
         return bool(re.search(re_pattern, re_string))
     except:
         return False
	"""
	SQLite3 backend for django.

	Python 2.3 and 2.4 require pysqlite2 (http://pysqlite.org/).

	Python 2.5 and later use the sqlite3 module in the standard library.
	"""

	from django.db.backends import *
	from django.db.backends.sqlite3.client import DatabaseClient
	from django.db.backends.sqlite3.creation import DatabaseCreation
	from django.db.backends.sqlite3.introspection import DatabaseIntrospection

	try:
	try:
	from sqlite3 import dbapi2 as Database
	except ImportError:
	from pysqlite2 import dbapi2 as Database
	except ImportError, e:
	import sys
	from django.core.exceptions import ImproperlyConfigured
	if sys.version_info < (2, 5, 0):
	module = 'pysqlite2'
	else:
	module = 'sqlite3'
	raise ImproperlyConfigured, "Error loading %s module: %s" % (module, e)

	try:
	import decimal
	except ImportError:
	from django.utils import _decimal as decimal # for Python 2.3

	DatabaseError = Database.DatabaseError
	IntegrityError = Database.IntegrityError

	Database.register_converter("bool", lambda s: str(s) == '1')
	Database.register_converter("time", util.typecast_time)
	Database.register_converter("date", util.typecast_date)
	Database.register_converter("datetime", util.typecast_timestamp)
	Database.register_converter("timestamp", util.typecast_timestamp)
	Database.register_converter("TIMESTAMP", util.typecast_timestamp)
	Database.register_converter("decimal", util.typecast_decimal)
	Database.register_adapter(decimal.Decimal, util.rev_typecast_decimal)
	if Database.version_info >= (2,4,1):
	# Starting in 2.4.1, the str type is not accepted anymore, therefore,
	# we convert all str objects to Unicode
	# As registering a adapter for a primitive type causes a small
	# slow-down, this adapter is only registered for sqlite3 versions
	# needing it.
	Database.register_adapter(str, lambda s:s.decode('utf-8'))

	class DatabaseFeatures(BaseDatabaseFeatures):
	# SQLite cannot handle us only partially reading from a cursor's result set
	# and then writing the same rows to the database in another cursor. This
	# setting ensures we always read result sets fully into memory all in one
	# go.
	can_use_chunked_reads = False

	class DatabaseOperations(BaseDatabaseOperations):
	def date_extract_sql(self, lookup_type, field_name):
	# sqlite doesn't support extract, so we fake it with the user-defined
	# function django_extract that's registered in connect().
	return 'django_extract("%s", %s)' % (lookup_type.lower(), field_name)

	def date_trunc_sql(self, lookup_type, field_name):
	# sqlite doesn't support DATE_TRUNC, so we fake it with a user-defined
	# function django_date_trunc that's registered in connect().
	return 'django_date_trunc("%s", %s)' % (lookup_type.lower(), field_name)

	def drop_foreignkey_sql(self):
	return ""

	def pk_default_value(self):
	return 'NULL'

	def quote_name(self, name):
	if name.startswith('"') and name.endswith('"'):
	return name # Quoting once is enough.
	return '"%s"' % name

	def no_limit_value(self):
	return -1

	def sql_flush(self, style, tables, sequences):
	# NB: The generated SQL below is specific to SQLite
	# Note: The DELETE FROM... SQL generated below works for SQLite databases
	# because constraints don't exist
	sql = ['%s %s %s;' % \
	(style.SQL_KEYWORD('DELETE'),
	style.SQL_KEYWORD('FROM'),
	style.SQL_FIELD(self.quote_name(table))
	) for table in tables]
	# Note: No requirement for reset of auto-incremented indices (cf. other
	# sql_flush() implementations). Just return SQL at this point
	return sql

	def year_lookup_bounds(self, value):
	first = '%s-01-01'
	second = '%s-12-31 23:59:59.999999'
	return [first % value, second % value]

	class DatabaseWrapper(BaseDatabaseWrapper):

	# SQLite requires LIKE statements to include an ESCAPE clause if the value
	# being escaped has a percent or underscore in it.
	# See http://www.sqlite.org/lang_expr.html for an explanation.
	operators = {
	'exact': '= %s',
	'iexact': "LIKE %s ESCAPE '\\'",
	'contains': "LIKE %s ESCAPE '\\'",
	'icontains': "LIKE %s ESCAPE '\\'",
	'regex': 'REGEXP %s',
	'iregex': "REGEXP '(?i)' \|\| %s",
	'gt': '> %s',
	'gte': '>= %s',
	'lt': '< %s',
	'lte': '<= %s',
	'startswith': "LIKE %s ESCAPE '\\'",
	'endswith': "LIKE %s ESCAPE '\\'",
	'istartswith': "LIKE %s ESCAPE '\\'",
	'iendswith': "LIKE %s ESCAPE '\\'",
	}

	def __init__(self, args, *kwargs):
	super(DatabaseWrapper, self).__init__(args, *kwargs)

	self.features = DatabaseFeatures()
	self.ops = DatabaseOperations()
	self.client = DatabaseClient()
	self.creation = DatabaseCreation(self)
	self.introspection = DatabaseIntrospection(self)
	self.validation = BaseDatabaseValidation()

	def _cursor(self, settings):
	if self.connection is None:
	if not settings.DATABASE_NAME:
	from django.core.exceptions import ImproperlyConfigured
	raise ImproperlyConfigured, "Please fill out DATABASE_NAME in the settings module before using the database."
	kwargs = {
	'database': settings.DATABASE_NAME,
	'detect_types': Database.PARSE_DECLTYPES \| Database.PARSE_COLNAMES,
	}
	kwargs.update(self.options)
	self.connection = Database.connect(**kwargs)
	# Register extract, date_trunc, and regexp functions.
	self.connection.create_function("django_extract", 2, _sqlite_extract)
	self.connection.create_function("django_date_trunc", 2, _sqlite_date_trunc)
	self.connection.create_function("regexp", 2, _sqlite_regexp)
	return self.connection.cursor(factory=SQLiteCursorWrapper)

	def close(self):
	from django.conf import settings
	# If database is in memory, closing the connection destroys the
	# database. To prevent accidental data loss, ignore close requests on
	# an in-memory db.
	if settings.DATABASE_NAME != ":memory:":
	BaseDatabaseWrapper.close(self)

	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".
	"""
	def execute(self, query, params=()):
	query = self.convert_query(query, len(params))
	return Database.Cursor.execute(self, query, params)

	def executemany(self, query, param_list):
	try:
	query = self.convert_query(query, len(param_list[0]))
	return Database.Cursor.executemany(self, query, param_list)
	except (IndexError,TypeError):
	# No parameter list provided
	return None

	def convert_query(self, query, num_params):
	return query % tuple("?" * num_params)

	def _sqlite_extract(lookup_type, dt):
	try:
	dt = util.typecast_timestamp(dt)
	except (ValueError, TypeError):
	return None
	return unicode(getattr(dt, lookup_type))

	def _sqlite_date_trunc(lookup_type, dt):
	try:
	dt = util.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 _sqlite_regexp(re_pattern, re_string):
	import re
	try:
	return bool(re.search(re_pattern, re_string))
	except:
	return False