> i am facing problem in joining three table...there are two columns common
> in two table..is it necessary to use both these two column..in where
> clauses.........
If you provide table definitions, it would be easier to say. But in the mean time you can read up
on joining table from the following link:
http://www.postgresql.org/docs/8.2/interactive/queries-table-expressions.html#QUERIES-JOIN
Regards,
Richard Broersma Jr.