Question

如何使用服务器端DataTable

在页脚上创建总行数

| Name  | Boy  | Girl |
| Boy1  |  -   |      |
| Girl1 |      |  -   |
| Boy2  |  -   |      |
| Total |  2   |  1   |

我使用此查询，但结果只显示1个数据（例如，应该是3个数据）

select name, sum(case when sex = "male" then 1 else 0 end) as boy, sum(case when sex = "female" then 1 else 0 end) as girl' from student;

谢谢

Answer 1

如果您的数据库支持ROLLUP功能，那么您可以尝试以下操作：

SELECT
    name,
    SUM(CASE WHEN sex = "male"   THEN 1 ELSE 0 END) AS boy,
    SUM(CASE WHEN sex = "female" THEN 1 ELSE 0 END) AS girl
FROM student
GROUP BY name
WITH ROLLUP

如果您的数据库不支持ROLLUP，那么可以使用UNION在底部添加记录总数：

SELECT
    name,
    SUM(CASE WHEN sex = "male"   THEN 1 ELSE 0 END) AS boy,
    SUM(CASE WHEN sex = "female" THEN 1 ELSE 0 END) AS girl
FROM student
GROUP BY name
UNION ALL
SELECT
    'total',
    SUM(CASE WHEN sex = "male"   THEN 1 ELSE 0 END),
    SUM(CASE WHEN sex = "female" THEN 1 ELSE 0 END)
FROM student
ORDER BY
    CASE WHEN name = 'total' THEN 1 ELSE 0 END,
    name

数据资源服务器端在页脚上显示具有特定值的列的计数结果

1 个答案: