DBI202Xuất hiện trong 1 đề thi
What does the UNION operator on sets do?
Các lựa chọn
AThe UNION operator sorts the selected result set.
BThe UNION operator combines the results of two or more queries into one result that includes distinctive rows from the queries.
CThe UNION operator combines the results of two or more queries into one result that includes all rows from the queries.
DThe UNION operator behaves the same as the JOIN SQL clause.