Your error handler routine starts automatically after a numbered error occurs. In many cases, the query that triggered the error is still active. Do not issue any query statements from inside your error handler routine because the application occasionally "hangs" or returns runtime errors.

The only embedded SQL statements you can safely issue from your error handler routine are:

The error handler called by IIseterr( ) handles numbered errors. It handles errors from the Ingres DBMS Server, the FRS, and the Ingres LIBQ; that is, errors known to the inquire_sql or inquire_frs statements. It does not handle 4GL statement errors or ABF/Vision runtime errors.

ABF or Vision starts the database before it sees your error handler declaration in the initialize section of your Top frame. Your application cannot "catch" database start-up errors. Neither your error handler routine nor the inquire_sql statement can catch these errors; Ingres simply issues an error message and your application exits.