how to link two table on part of field

Hello every one,



I have two tables (A) and (B).



Table (A) contains key-field name "position1".

table (B) contains key-filed name "position2".



Please advise how to make a link between key-field "position1" and part of key-field "position2".



Hope the question is clear..



Thanks in advance.

jscodm

how to link two table on part of field