⑴Cost The cost assigned to each step of the query plan by the CBO. The CBO works bygenerating many different execution paths/plans for the same query and assigns a cost to each and every one. The query plan with the lowest cost wins. In the full outer join example,we can see the total cost for this query is 10.⑵Card Card is short for Cardinality. It is the estimated number of rows that will flow outof a given query plan step. In the full outer join example, we can see the optimizer expectsthere to be 327 rows in EMP and 4 rows in DEPT.⑶Bytes The size in bytes of the data the CBO expects each step of the plan to return.This is dependent on the number of rows (Card) and the estimated width of the rows.