Connection is busy with results for another hstmt

Question

HI guys,

I'm using ODBC driver from WinXP SP2 with SQL Server 2005 Express (on my machine for test) and SQL Server 2005 Standard (on the production machine).

With SQL Server 2005 Express I've no problem, but with SQL Server 2005 Standard, in some query, I get "Connection is busy with results for another hstmt".

I'm working with VisualStudio 2003 with standard CDatabase and CRecordSet MFC classes.

I looked for an advice in the Microsoft KB but I found only Service Pack for SQL Server 2000 !

Everything could be useful !

Thanks a lot!

Bye, Domenico

Answer 1

You can avoid this error message by switching to the SQL Server 2005 ODBC driver, 'SQL Native Client' and enabling the MARS (Multiple Active Result Sets feature). There is more information in Books Online and also here http://blogs.msdn.com/dataaccess/archive/2005/08/02/446894.aspx

 

Answer 2

I need to enable MARS using ODBC & VB6  () but I have not been able to find where the constants in the statement below are defined. If anyone could help me find the values for the constants it would be greatly appriecated

    SQLSetConnectAttr(hdbc, SQL_COPT_SS_MARS_ENABLED,SQL_MARS_ENABLED_YES, SQL_IS_UINTEGER);

Answer 3

sqlncli.h has the constants you are looking for.

 

It is in %program files%\Microsoft SQL Server\90\SDK\Include

 

Lib is at %program files%\Microsoft SQL Server\90\SDK\Lib

Answer 4

Alternatively you can control MARS from the connection string. In OLE DB it's "MarsConn=yes", for ADO it's "MARS Connection=true" and for ODBC it's "MARS_Connection=yes".