从 SQL 查询中过滤数据

Question

In the below table, I need to exclude CategoryID=1002 and Gender='KIDS' record from the table and return other records.

+------+--------+
|  ID  | Gender |
+------+--------+
| 1001 | MENS   |
| 1002 | MENS   |
| 1001 | WOMENS |
| 1002 | WOMENS |
| 1001 | KIDS   |
| 1002 | KIDS   |
+------+--------+

Expected results:

+------+--------+
|  ID  | Gender |
+------+--------+
| 1001 | MENS   |
| 1002 | MENS   |
| 1001 | WOMENS |
| 1002 | WOMENS |
| 1001 | KIDS   |
+------+--------+

Answer 1

You could use a CASE expression as

SELECT *
FROM
(
  VALUES
  (1001,    'MENS'),
  (1002,    'MENS'),
  (1001,    'WOMENS'),
  (1002,    'WOMENS'),
  (1001,    'KIDS'),
  (1002,    'KIDS')
) T(Id, Gender)
WHERE CASE WHEN ID = 1002 AND Gender = 'KIDS' THEN 1 ELSE 0 END = 0;

Online Demo

Answer 2

I don't recommend using case expressions in the where clause, because that can affect the optimizer.

This is easily expressed as boolean logic:

where not (CategoryID = 1002 and Gender = 'KIDS')

or:

where CategoryID <> 1002 or Gender <> 'KIDS'