mssql+zxjdbc support

original patch from Victor Ng
fixes #1505

3 files changed, 69 insertions, 3 deletions

diff --git a/lib/sqlalchemy/dialects/mssql/__init__.py b/lib/sqlalchemy/dialects/mssql/__init__.py
index e3a829047..292320568 100644
--- a/lib/sqlalchemy/dialects/mssql/__init__.py
+++ b/lib/sqlalchemy/dialects/mssql/__init__.py
@@ -1,3 +1,3 @@
-from sqlalchemy.dialects.mssql import base, pyodbc, adodbapi, pymssql
+from sqlalchemy.dialects.mssql import base, pyodbc, adodbapi, pymssql, zxjdbc
 
-base.dialect = pyodbc.dialect
\ No newline at end of file
+base.dialect = pyodbc.dialect
diff --git a/lib/sqlalchemy/dialects/mssql/zxjdbc.py b/lib/sqlalchemy/dialects/mssql/zxjdbc.py
new file mode 100644
index 000000000..28b9547d8
--- /dev/null
+++ b/lib/sqlalchemy/dialects/mssql/zxjdbc.py
@@ -0,0 +1,64 @@
+"""Support for the Microsoft SQL Server database via the zxjdbc JDBC
+connector.
+
+JDBC Driver
+-----------
+
+Requires the jTDS driver, available from: http://jtds.sourceforge.net/
+
+Connecting
+----------
+
+URLs are of the standard form of
+``mssql+zxjdbc://user:pass@host:port/dbname[?key=value&key=value...]``.
+
+Additional arguments which may be specified either as query string
+arguments on the URL, or as keyword arguments to
+:func:`~sqlalchemy.create_engine()` will be passed as Connection
+properties to the underlying JDBC driver.
+
+"""
+from sqlalchemy.connectors.zxJDBC import ZxJDBCConnector
+from sqlalchemy.dialects.mssql.base import MSDialect, MSExecutionContext
+from sqlalchemy.engine import base
+
+class MS_zxjdbcExecutionContext(MSExecutionContext):
+
+    _embedded_scope_identity = False
+
+    def pre_exec(self):
+        super(MS_zxjdbcExecutionContext, self).pre_exec()
+        # scope_identity after the fact returns null in jTDS so we must
+        # embed it
+        if self._select_lastrowid and self.dialect.use_scope_identity:
+            self._embedded_scope_identity = True
+            self.statement += "; SELECT scope_identity()"
+
+    def post_exec(self):
+        if self._embedded_scope_identity:
+            while True:
+                try:
+                    row = self.cursor.fetchall()[0]
+                    break
+                except self.dialect.dbapi.Error, e:
+                    self.cursor.nextset()
+            self._lastrowid = int(row[0])
+
+        if (self.isinsert or self.isupdate or self.isdelete) and self.compiled.returning:
+            self._result_proxy = base.FullyBufferedResultProxy(self)
+
+        if self._enable_identity_insert:
+            table = self.dialect.identifier_preparer.format_table(self.compiled.statement.table)
+            self.cursor.execute("SET IDENTITY_INSERT %s OFF" % table)
+
+
+class MS_zxjdbc(ZxJDBCConnector, MSDialect):
+    jdbc_db_name = 'jtds:sqlserver'
+    jdbc_driver_name = 'net.sourceforge.jtds.jdbc.Driver'
+
+    execution_ctx_cls = MS_zxjdbcExecutionContext
+
+    def _get_server_version_info(self, connection):
+        return tuple(int(x) for x in connection.connection.dbversion.split('.'))
+
+dialect = MS_zxjdbc
diff --git a/lib/sqlalchemy/test/requires.py b/lib/sqlalchemy/test/requires.py
index f3f4ec191..be6ae9594 100644
--- a/lib/sqlalchemy/test/requires.py
+++ b/lib/sqlalchemy/test/requires.py
@@ -70,7 +70,9 @@ def independent_connections(fn):
     # ODBC as well.
     return _chain_decorators_on(
         fn,
-        no_support('sqlite', 'no driver support')
+        no_support('sqlite', 'no driver support'),
+        exclude('mssql', '<', (9, 0, 0),
+                'SQL Server 2005+ is required for independent connections'),
         )
 
 def row_triggers(fn):