The PL/SQL Challenge quiz for 10 September - 16 September 2016 explored the different ways you can obtain the error message / stack in PL/SQL. Note: an error stack is a sequence of multiple error messages that can occur when an exception is propagated and re-raised through several layers of nested blocks. The three ways are: SQLERRM - The original, traditional and (oddly enough) not currently recommended function to get the current error message. Not recommended because the next two options avoid a problem which you are unlikely to run into: the error stack will be truncated at 512 bytes, and you might lose some error information. DBMS_UTILITY.FORMAT_ERROR_STACK - Returns the error message / stack, and will not truncate your string like SQLERRM will. UTL_CALL_STACK API - Added in Oracle Database 11g, the UTL_CALL_STACK package offers a comprehensive API into the execution call stack, the error stack and the error backtrace. Note: check out this LiveSQL script if you'd like to explore more of the nuances between SQLERRM and DBMS_UTILITY.FORMAT_ERROR_STACK. Other helpful resources regarding error management in PL/SQL: Nine Good to Knows for PL/SQL Error Management PL/SQL Error Handling (doc) Finally, here's the code from our quiz that you can copy/paste into your editor to check out these alternatives. CREATE OR REPLACE PROCEDURE plch_check_balance ( balance_in IN NUMBER) AUTHID DEFINER IS BEGIN IF balance_in < 0 THEN RAISE VALUE_ERROR; END IF; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.put_line (SQLERRM); END; / BEGIN plch_check_balance (-1); END; / CREATE OR REPLACE PROCEDURE plch_check_balance ( balance_in IN NUMBER) AUTHID DEFINER IS BEGIN IF balance_in < 0 THEN RAISE VALUE_ERROR; END IF; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.put_line (DBMS_UTILITY.format_error_stack); END; / BEGIN plch_check_balance (-1); END; / CREATE OR REPLACE PROCEDURE plch_check_balance ( balance_in IN NUMBER) AUTHID DEFINER IS BEGIN IF balance_in < 0 THEN RAISE VALUE_ERROR; END IF; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.put_line ( 'ORA-' || TO_CHAR (UTL_CALL_STACK.error_number (1), 'fm00000') || ': ' || UTL_CALL_STACK.error_msg (1)); END; / BEGIN plch_check_balance (-1); END; / DROP PROCEDURE plch_check_balance /
↧