Troubleshooting the SQL Server ODBC Driver

Troubleshooting the Microsoft® SQL Server™ ODBC driver should include a review of the following issues:

• If applications prepare a lot of SQL, it is recommended that these clients release the SQL as soon as possible to free memory. For more information, see Prepared Execution.
• Few or no servers appear in the Register Server Wizard in SQL Server Enterprise Manager after either clicking Next in the Welcome dialog box, or executing osql-L.

  Microsoft Windows NT® enumerates servers, but Microsoft Windows® 95/98 does not. On Windows 95/98, the only servers enumerated either by using the Register Server Wizard or by executing osql-L are those servers configured explicitly using the Client Network Utility.

  Windows NT enumerates servers by network broadcast, listening for a fixed time period. Only those servers either added explicitly or those receiving the broadcast and replying within the specified time limit are enumerated.

  Therefore, on a Windows NT server, it is possible to see a large list of enumerated servers at one point in time, and then see a smaller list of enumerated servers just a few seconds later. This absence of enumerated servers can be caused by one or more temporarily busy or unavailable network computers.

• On Windows 95/98, a connection cannot be established to any ODBC application if the Shared Memory Net-Library file named dbmsshrn.dll was either renamed or deleted. This Shared Memory Net-Library file is required for local connections.
• All driver-specific connection attributes are reset when an application uses connection pooling. After a connection is complete, an application using connection pooling must set all driver-specific connection attributes.
• To eliminate the row count messages from DML statements inside a procedure, use SET NOCOUNT ON as the first statement in the procedure.
• Character and binary parameters are padded to the size specified in SQLBindParameter. To disable, clear the AnsiNPW check box.
• The code page of the server must be installed on the client workstation unless automatic translation is disabled.
• Parameters must be specified as SQL_PARAM_INPUT unless the parameters are used with a stored procedure and declared as OUTPUT parameters.
• When a 2.65 or earlier version of the SQL Server ODBC driver is used and connected to a server running SQL Server 7.0, the server classifies the application as a pre-SQL Server 7.0 client and does not support certain features introduced in SQL Server 7.0. For more information, see Connecting Early Version Clients to SQL Server 7.0.

For more information about the changes from the version 2.0 ODBC driver to the version 3.0 ODBC driver, see the Microsoft ODBC 3.0 Programmer's Reference and SDK Guide.

See Also