return setof : alternatives to holder table

Hello List,

I have a plpgsql function returning a set of records.  The record is
effectively a join of some tables.

For example, table a (column a1,column a2,column a3,column a4)

table b(column b1,column b2,column b4)

I am returning a set of (a2,a4,b2). What I do now is to create a empty table

foo(column a2,column a4,column b2)

then in my function I have

record r foo%rowtype

I'm not happy with this solution because this foo tables has to be kept around

Thanks for any better solution to this

mr.wu