>Cetin
>
>You are refering to a recursive query, which I (I admit the mischaracterization as recursive CTEs can be use in creating records as well) referred to as for solving hierarchical problems. This is where I almost exclusively use them for.
>
>The challenge was to find me an example where using CTE as a subquery would lead to any significant advantage.
>
>Walter,

OK now it is your turn to write this without a CTE (a sample from postgreSQL documentation):

WITH w AS (
    SELECT key, very_expensive_function(val) as f FROM some_table
)
SELECT * FROM w AS w1 JOIN w AS w2 ON w1.f = w2.f;