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  • mysql自定义排序

    场景

    业务需要,优惠券列表要求按类型进行排序,但是,类型并不是顺序的,即order by是解决不了问题的

    建表

    CREATE TABLE `custom_sort`  (
      `id` int(20) NOT NULL AUTO_INCREMENT,
      `name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_german2_ci NOT NULL,
      `type` tinyint(1) NOT NULL,
      PRIMARY KEY (`id`) USING BTREE,
      INDEX `so`(`type`) USING BTREE
    ) ENGINE = InnoDB AUTO_INCREMENT = 8 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_german2_ci ROW_FORMAT = Dynamic;
    

    插入数据

    INSERT INTO `custom_sort` VALUES (1, '刘一', 1);
    INSERT INTO `custom_sort` VALUES (2, '陈二', 2);
    INSERT INTO `custom_sort` VALUES (3, '张三', 3);
    INSERT INTO `custom_sort` VALUES (4, '李四', 2);
    INSERT INTO `custom_sort` VALUES (5, '王五', 5);
    INSERT INTO `custom_sort` VALUES (6, '赵六', 0);
    INSERT INTO `custom_sort` VALUES (7, '孙七', 7);
    

    表结构数据

    解决方案

    field函数

    SELECT * FROM `custom_sort` ORDER BY FIELd(type,1,3) desc,type
    

    case when then

    SELECT * FROM `custom_sort` ORDER BY CASE WHEN type= 3 THEN 0 WHEN type= 1 THEN 1 else 2 END ,type asc
    

    查询结果

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  • 原文地址:https://www.cnblogs.com/chywx/p/12163097.html
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