**# EXAMPLE SQL CTEs:**

WITH cte_transations AS (SELECT
-- the result set of a query which exists temporarily and for use only 
-- within the context of a larger query.
-- the result of a CTE is not stored and exists only for the duration of the query.
                               account_id,
                               sum(amount),
                               sum(balance)
						              FROM bank.trans
                         GROUP BY 1),
	   cte_account AS (SELECT 
                          *
					           FROM cte_transactions ct
                    JOIN bank.account a
                    USING (account_id))