Using stored functions in SQL WHERE clauses

I am maintaining some PL/SQL code that was migrated from Oracle 5->6->7 and contains a mixture of VARCHAR and fixed-length CHAR fields. This is creating some difficulty since most of my queries involve at least one condition that looks like "RPAD(field,len) = value". My chief concern is maintainability since the decision was made to incrementally migrate the database from mostly VARCHAR to mixed VARCHAR and CHAR fields.

I would like to store a function to use for all text field equality conditions and while I have successfully stored such a function and can access it elsewhere, SQLPlus balks at calling it from a where clause. I am beginning to think this cannot be done, though all documentation I've consulted is ambiguous about which functions can be called this way.

Can anyone suggest a way to do this or an alternative? Received on Mon Nov 14 1994 - 16:11:58 CET