diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/sqlalchemy/dialects/mssql/base.py | 45 |
1 files changed, 30 insertions, 15 deletions
diff --git a/lib/sqlalchemy/dialects/mssql/base.py b/lib/sqlalchemy/dialects/mssql/base.py index 814fc7799..0399cbd90 100644 --- a/lib/sqlalchemy/dialects/mssql/base.py +++ b/lib/sqlalchemy/dialects/mssql/base.py @@ -1786,21 +1786,36 @@ class MSDialect(default.DefaultDialect): raise NotImplementedError( "Can't fetch isolation level prior to SQL Server 2005") - cursor = connection.cursor() - cursor.execute(""" - SELECT CASE transaction_isolation_level - WHEN 0 THEN NULL - WHEN 1 THEN 'READ UNCOMMITTED' - WHEN 2 THEN 'READ COMMITTED' - WHEN 3 THEN 'REPEATABLE READ' - WHEN 4 THEN 'SERIALIZABLE' - WHEN 5 THEN 'SNAPSHOT' END AS TRANSACTION_ISOLATION_LEVEL - FROM sys.dm_exec_sessions - where session_id = @@SPID - """) - val = cursor.fetchone()[0] - cursor.close() - return val.upper() + views = ("sys.dm_exec_sessions", "sys.dm_pdw_nodes_exec_sessions") + for view in views: + cursor = connection.cursor() + try: + cursor.execute(""" + SELECT CASE transaction_isolation_level + WHEN 0 THEN NULL + WHEN 1 THEN 'READ UNCOMMITTED' + WHEN 2 THEN 'READ COMMITTED' + WHEN 3 THEN 'REPEATABLE READ' + WHEN 4 THEN 'SERIALIZABLE' + WHEN 5 THEN 'SNAPSHOT' END AS TRANSACTION_ISOLATION_LEVEL + FROM %s + where session_id = @@SPID + """ % view) + val = cursor.fetchone()[0] + except self.dbapi.Error as err: + continue + else: + return val.upper() + finally: + cursor.close() + + util.warn( + "Could not fetch transaction isolation level, " + "tried views: %s; final error was: %s" % (views, err)) + raise NotImplementedError( + "Can't fetch isolation level on this particular " + "SQL Server version" + ) def initialize(self, connection): super(MSDialect, self).initialize(connection) |