Error messages from IQ

Sybase IQ sometimes gives some confusing error messages. Look at this one:

Exception Thrown from db_txnInfo.cxx:833, Err# 1, tid 143 origtid 143
   O/S Err#: 0, ErrID: 1025 (db_catalogException); SQLCode: -1000029, SQLState: 'QDA29', Severity: 14
[20689]: Cannot open the requested object for write in the current transaction (1722819).   Another user has write access in transaction 1722818. 
-- (db_txnInfo.cxx 833)

When you get this message in the IQ message file, it means that only a single session can update the same table at the same time. Although the text of the message indicates that an exception in the catalog was detected, you will see this error also for base IQ tables.