Joining two tables based on column having two different data types

Hi,

I need to join two tables based on a column which is having different data types in the tables.

I have a column WorkGroupCode with Numeric data type in Table A and with Character Datatype in Table B.Is there any way we can change either of the datatypes to one  ( Numeric to Character or viceversa) and perform the join using IDT in Business Objects. Is there we can do it in IDT instead of changing at the database level.

Please advice!