php - 两种情况如何设置 "ORDER BY"？

Question

在 mysql 中，我需要为两种情况设置“ORDER BY”:name 或 mod_1，具体取决于用户在组合框中选择的内容。我的查询是:

SELECT
    name,
    SUM(IF(mod = 1, 1, 0)) AS mod_1,
    SUM(IF(mod = 2, 1, 0)) AS mod_2,
    SUM(IF(mod = 3, 1, 0)) AS mod_3
FROM
    DW_RM_Log
WHERE
    ...
ORDER BY
    name (or mod_1 DESC)

是否可以在 mysql 中执行此操作，或者我需要在 php 中对其进行编码？或者两者兼而有之？

Answer 1

无聊到为你做这件事:

$q = "SELECT
    name,
    SUM(IF(mod = 1, 1, 0)) AS mod_1,
    SUM(IF(mod = 2, 1, 0)) AS mod_2,
    SUM(IF(mod = 3, 1, 0)) AS mod_3
FROM
    DW_RM_Log
WHERE
    ...
ORDER BY ";

if ($x) {
    $q .= "name DESC";
} else {
    $q .= "mod_1 DESC";
}
 //run $q!