Thought I'd pose this problem here, as it seems rather problematical in
AS/400 SQL

Scenario is that there are two tables: F1 and F2.

F1 has columns A, B, P,Q
F2 has columns C, D, R, S

They are related in that for each row in F1 there is a corresponding row in
F2.
joined on F1.A = F2.C and F1.B = F2.D

Requirement is to update P & Q in F1 from R & S in corresponding row of F2
when either F1.P <> F2.R or F1.Q <> F2.S

Deleting rows in F1 where this case is true is an easy EXISTS test.

But how should an Update be done?

I can do it in MS SQL server, using an UPDATE FROM construct, but this is
rejected as syntactically invalid on the AS/400.

So can anyone give me an SQL statement to do this on an AS/400 please?

Thanks in advance :-)