FreeTDS Development Group

["James K. Lowden" <jklowden AT freetds.org>]

Ken Collins wrote:
> 
> dbcmd(dbproc,sql); // sql = "SELECT * FROM [foobar]"
> dbsqlsend(dbproc);
> dbsqlok(dbproc);
> 
> I can never get dbsqlexec or dbsqlok to return a status, just seems my
> program stops at that point. So the next time I come back around to
> putting something in the command buffer and executing it, I get a
> "Attempt to initiate a new Adaptive Server operation with results
> pending" error. 

http://manuals.sybase.com/onlinebooks/group-cnarc/cng1110e/dblib/@Generic__BookTextView/40525;pt=39614

        "Once dbsqlexec returns SUCCEED, the application must call dbresults 
to
process the results."

The library does not know that the server returned no results; it stopped
listening when the SQL was acknowledged.  Call dbresults() to confirm
there's nothing pending before issuing your next query.  

N.B.  The library can know, because the TDS_DONE packet indicates whether
or not more results follow.  That's how it knows whether to attempt to
read more data from the stream.  The state management might be a little
too conservative in this case, even if it's within spec.  

HTH.  

--jkl