User's Guide

Part II. Tutorials

Chapter 6. Using Character-Mode ISQL

The Ctrl+Breakcombination is used to abort a command.

A Stop operation stops current processing and prompts for the next command. If a command file was being processed, you are prompted for an action to take (Stop command file, Continue, or Exit ISQL). These actions can be controlled with the ISQL ON_ERROR option.

  For more information on ISQL options, see "SET OPTION statement".

When an abort is detected, one of three different errors will be reported depending upon when the abort is detected.

• If the abort is detected when ISQL is processing the request (as opposed to the database engine), then the following message is displayed:

       ISQL command terminated by user
  

• ISQL stops processing immediately and the database transaction is left alone.
• If the abort is detected while the database engine is processing a data definition command (CREATE, DROP, ALTER, etc.), the following message is displayed: Terminated by user---transaction rolled back Since data definition commands all perform a COMMIT automatically before the command starts, the effect of the ROLLBACK is to just cancel the current command.
• This message also occurs when the database engine is running in bulk operations mode executing a command that modifies the database (INSERT, UPDATE, and DELETE). In this case, ROLLBACK cancels not only the current command, but everything that has been done since the last COMMIT. In some cases, it may take a considerable amount of time for the database engine to perform the automatic ROLLBACK.
• If the abort is detected by the database engine while processing a standard data manipulation command (SELECT, INSERT, DELETE, etc.) and the engine is not running in bulk operations mode, then the following message is displayed. Statement interrupted by user The effects of the current command are undone, but the rest of the transaction is left intact.