MSQuery ErrMsg: "Unable to Retrieve Values" Using DEC Driver

• Microsoft Query for Windows, versions 1.0

SUMMARY

If you are using Microsoft Query to access a Digital Equipment Corporation (DEC) RDB database using version 1.x of the DEC ODBC driver, you may receive the following error message:

   Unable to retrieve values

MORE INFORMATION

If the above error message occurs and you are using versions 1.0 or 1.1 of the DEC ODBC driver, you can change an entry in the [DEC ODBC driver] section of the WIN.INI file. The entry should be changed from FETCHAHEAD=YES to FETCHAHEAD=NO. This entry tells the DEC ODBC driver how to send data communication packets back and forth between the database and Microsoft Query.

Normally, when you fetch records from the database, it will put each record into its own packet. This behavior will occur if FETCHAHEAD is turned off. You can turn the FETCHAHEAD option on to allow the DEC RDB database to put as many rows as can fit into a single network packet. Turning FETCHAHEAD on will keep the records from splitting up into more than one packet.

You may see this packet-splitting issue if you are using earlier versions of SQLServices (the client server part of RDB) with the TCP/IP network protocol. If turning off the FETCHAHEAD option changes the symptom, you may have a packet split problem.

The DEC ODBC driver included in this article is manufactured by Digital Equipment Corp., a vendor independent of Microsoft; we make no warranty, implied or otherwise, regarding this product's performance or reliability.