Serious errors

Errors that set SQLCODE to a negative value or SQLSTATE to a value that begins with anything other than 00, 01, or 02 are usually serious. Programs that you have developed and that are in production should rarely report these errors. Nevertheless, it is difficult to anticipate every problematic situation, so your program must be able to deal with these errors.

For example, a query can return error -206, which means that a table specified in the query is not in the database. This condition occurs if someone dropped the table after the program was written, or if the program opened the wrong database through some error of logic or mistake in input.