Enabling/disabling SQL interruption

The OPTIONS SQL INTERRUPT instruction enables or disables SQL statement interruption.

Syntax

OPTIONS SQL INTERRUPT { ON | OFF }

Usage

The OPTIONS SQL INTERRUPT instruction controls interruption event detection during the execution of long running SQL statements.

By default, SQL interruption is off.

Pay attention to the fact that not all database servers support SQL interruption.

Depending on the type of database server and client, SQL interruption handling may require additional overhead. Consider enabling SQL interruption only for SQL queries that can take a while to execute or can be blocked for a long time because of concurrent access (locks).

If an SQL statement is interrupted, sqlca.sqlcode is set to -213 and the runtime system raises an error. Use a TRY/CATCH block or WHENEVER ERROR CONTINUE to trap this SQL error.

Example

MAIN
    DEFINE cnt INTEGER
    DEFER INTERRUPT -- Do not stop if interrupt signal is caught
    CONNECT TO "mydb"
    WHENEVER ERROR CONTINUE -- Continue in case of SQL interrupt error
    OPTIONS SQL INTERRUPT ON -- Enable SQL interruption
    SELECT COUNT(*) INTO cnt FROM stock -- Long running query 
    OPTIONS SQL INTERRUPT OFF -- Disable SQL interruption
    WHENEVER ERROR STOP -- Reset default exception handler
    IF sqlca.sqlcode == -213 THEN
       DISPLAY "SQL Statement interrupted by user"
    END IF
END MAIN