Best Practises for Error Handling

Question

Hello
I have a PHP front end application and for now an Oracle database in the backend. User defined errors are returned back to PHP front end using RAISE_APPLICATION_ERROR(-20000,'error msg'), the PHP displays the message to the user. We have a problem where we are now going to provide a French version on the application and are stuck at what we are to do with the error messages.
What is the common practise for this?

Answer 1

Don't reinvent the wheel. Oracle provides built-in error globalization.
http://www.morganslibrary.org/reference/pkgs/utl_lms.html
SQL> set serveroutput on
SQL> DECLARE
  2   s VARCHAR2(32767);
  3   i PLS_INTEGER;
  4  BEGIN
  5    i := utl_lms.get_message(26052,'rdbms','ora','french', s);
  6 
  7    dbms_output.put_line('before format, message is: ' || s);
  8 
  9    dbms_output.put_line('formatted message is: '|| utl_lms.format_message(s, 96, 'my_string'));
10  END;
11  /
before format, message is: Type %d non pris en charge pour l'expression SQL sur la colonne %s.
formatted message is: Type 96 non pris en charge pour l'expression SQL sur la colonne my_string.
PL/SQL procedure successfully completed.
SQL> ed
Wrote file afiedt.buf
  1  DECLARE
  2   s VARCHAR2(32767);
  3   i PLS_INTEGER;
  4  BEGIN
  5    i := utl_lms.get_message(26052,'rdbms','ora','german', s);
  6    dbms_output.put_line('before format, message is: ' || s);
  7    dbms_output.put_line('formatted message is: '|| utl_lms.format_message(s, 96, 'my_string'));
  8* END;
  9  /
before format, message is: Nicht unterstützter Typ %d für SQL-Ausdruck in Spalte %s.
formatted message is: Nicht unterstützter Typ 96 für SQL-Ausdruck in Spalte my_string.
PL/SQL procedure successfully completed.If you are writing your own messages then Tubby's recommendation is best but I'd be inclined not to put the messages into a table but rather to put them into a package header as constants which minimizes I/O overhead.