Question

我有一个包含多个具有布尔值的字段的表。

只有当所有3个字段都为真时，才需要合并3个字段。

我在考虑JOIN，但看起来它无法满足我的需求。

------------------------------------------------------------
| Email address| permission1 | permission2 | permission3
------------------------------------------------------------
| test@test.com|     1       |      0      |      1
------------------------------------------------------------
| test2@test.com|     1      |      1      |      1
------------------------------------------------------------

我希望结果可能在新表中看起来像这样：

--------------------------------
| Email address| permissionMerge 
--------------------------------
| test@test.com|     0       | 
--------------------------------
| test2@test.com|     1      | 
--------------------------------

Answer 1

您可以使用CASE syntax

SELECT `email address`,
CASE WHEN `permission1` = 1 
     AND  `permission2` = 1 
     AND `permission3` = 1 
THEN 1 
ELSE 0 END AS 'permissionMerge'
FROM `Table`

您也可以这样做：

SELECT `email address`,
CASE WHEN SUM(`permission1`,`permission2`,`permission3`) = 3   
THEN 1 
ELSE 0 END AS 'permissionMerge'
FROM `Table`
GROUP BY `email address`

Answer 2

Select `Email adderss`,(permission1 and permission2 and permission3) as permissionMerge from table

Answer 3

根据数据的质量，您可以轻而易举地完成以下任务：

SELECT address,
CASE SUM(permission1, permission2, permission3)
    WHEN 3 THEN 1
    ELSE 0
END AS permissionMerge 
FROM undisclosed_table

......或者你需要更强大的东西：

SELECT address,
CASE
    WHEN permission1 IS TRUE AND permission2 IS TRUE AND permission3 IS TRUE THEN 1
    ELSE 0
END AS permissionMerge 
FROM undisclosed_table

您可以使用以下内容生成新表：

CREATE TABLE table_with_duplicate_data
SELECT address,
CASE
    WHEN permission1 IS TRUE AND permission2 IS TRUE AND permission3 IS TRUE THEN 1
    ELSE 0
END AS permissionMerge 
FROM undisclosed_table

...以为我会反对它：它只会浪费存储空间，你需要保持数据的最新状态。如果输入太多，您可以创建一个view或（自MySQL / 5.7.5开始）generated column。

有没有办法在MySQL中合并布尔值字段？

3 个答案: