Question

我有一个包含4个字段的MySQL数据库：

id | planchanged | dataremoved | rolloverenabled |
1  | Yes         | Yes         | Yes             |
2  | NULL        |             |                 |
3  |             | Yes         |                 |
4  | Yes         |             | Yes             |
5  |             |             | NULL            |

如何查询此数据库以仅显示在这三个字段中没有全部为“是”的记录。另请注意，某些字段可能 Null 。因此，根据该示例，我的结果应显示记录2,3,4和5。

Answer 1

你可以这样做

SELECT * FROM TableName 
WHERE coalesce(planchanged,'-') <> 'Yes' OR 
coalesce(dataremoved,'-') <> 'Yes' OR
coalesce(rolloverenabled,'-') <>'Yes'

SQL FIDDLE DEMO

Answer 2

SELECT * 
FROM yourTableName 
WHERE planchanged IS NULL OR planchanged <> 'Yes' 
OR dataremoved IS NULL OR dataremoved <> 'Yes' 
OR rolloverenabled IS NULL OR rolloverenabled <> 'Yes'

SQL Fiddle

Answer 3

SELECT * 
FROM  yourTableName 
WHERE planchanged IS NULL 
  OR  dataremoved IS NULL 
  OR  rolloverenabled IS NULL 
  OR  planchanged <> 'Yes' 
  OR  dataremoved <> 'Yes' 
  OR  rolloverenabled <> 'Yes'

如果所有三个字段都为“是”，则隐藏SQL结果

3 个答案: