diff options
Diffstat (limited to 'django/db/backends/oracle/base.py')
| -rw-r--r-- | django/db/backends/oracle/base.py | 43 |
1 files changed, 42 insertions, 1 deletions
diff --git a/django/db/backends/oracle/base.py b/django/db/backends/oracle/base.py index 231f4d5d62..442378cd28 100644 --- a/django/db/backends/oracle/base.py +++ b/django/db/backends/oracle/base.py @@ -365,9 +365,24 @@ WHEN (new.%(col_name)s IS NULL) return super(DatabaseOperations, self).combine_expression(connector, sub_expressions) +class _UninitializedOperatorsDescriptor(object): + + def __get__(self, instance, owner): + # If connection.operators is looked up before a connection has been + # created, transparently initialize connection.operators to avert an + # AttributeError. + if instance is None: + raise AttributeError("operators not available as class attribute") + # Creating a cursor will initialize the operators. + instance.cursor().close() + return instance.__dict__['operators'] + + class DatabaseWrapper(BaseDatabaseWrapper): vendor = 'oracle' - operators = { + operators = _UninitializedOperatorsDescriptor() + + _standard_operators = { 'exact': '= %s', 'iexact': '= UPPER(%s)', 'contains': "LIKE TRANSLATE(%s USING NCHAR_CS) ESCAPE TRANSLATE('\\' USING NCHAR_CS)", @@ -382,6 +397,16 @@ class DatabaseWrapper(BaseDatabaseWrapper): 'iendswith': "LIKE UPPER(TRANSLATE(%s USING NCHAR_CS)) ESCAPE TRANSLATE('\\' USING NCHAR_CS)", } + _likec_operators = _standard_operators.copy() + _likec_operators.update({ + 'contains': "LIKEC %s ESCAPE '\\'", + 'icontains': "LIKEC UPPER(%s) ESCAPE '\\'", + 'startswith': "LIKEC %s ESCAPE '\\'", + 'endswith': "LIKEC %s ESCAPE '\\'", + 'istartswith': "LIKEC UPPER(%s) ESCAPE '\\'", + 'iendswith': "LIKEC UPPER(%s) ESCAPE '\\'", + }) + def __init__(self, *args, **kwargs): super(DatabaseWrapper, self).__init__(*args, **kwargs) @@ -426,6 +451,22 @@ class DatabaseWrapper(BaseDatabaseWrapper): cursor.execute("ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS' " "NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF' " "NLS_TERRITORY = 'AMERICA'") + + if 'operators' not in self.__dict__: + # Ticket #14149: Check whether our LIKE implementation will + # work for this connection or we need to fall back on LIKEC. + # This check is performed only once per DatabaseWrapper + # instance per thread, since subsequent connections will use + # the same settings. + try: + cursor.execute("SELECT 1 FROM DUAL WHERE DUMMY %s" + % self._standard_operators['contains'], + ['X']) + except utils.DatabaseError: + self.operators = self._likec_operators + else: + self.operators = self._standard_operators + try: self.oracle_version = int(self.connection.version.split('.')[0]) # There's no way for the DatabaseOperations class to know the |