To override precedence, use parentheses. Operations in parentheses are performed first.
For example, consider the following form:
( ( SELECT statement_1 UNION SELECT statement_2 ) EXCEPT ( SELECT statement_3 UNION SELECT statement_4 ) ) EXCEPT SELECT statement_5 INTERSECT SELECT statement_6;
The following list explains the precedence of operators for this example.
- UNION SELECT statement _1 and SELECT statement _2.
- UNION SELECT statement _3 and SELECT statement _4.
- Subtract the result of the second UNION from the result of the first UNION.
- INTERSECT SELECT statement _5 and SELECT statement _6.
- Subtract the INTERSECT result from the remainder of the UNION operations.