Can a later CTE see an earlier one?

Question

Accepted Answer

CTEs in a WITH clause are processed in order, so each one can build on the ones before it. This is what makes chained CTEs so powerful for step-by-step data transformations - you can filter in cte_a, then aggregate in cte_b, then rank in cte_c, each step referring to the previous. The only restriction is that a non-recursive CTE cannot reference itself. Forward references (cte_a referencing cte_b defined later) are not allowed.