MYSQL case when 条件判断

1、多个字段的判断，case 后不指定字段，使用when来判断多个字段

　　

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SELECT     A.id,NAME,description,     CASE          WHEN   ISNULL(apply_status) THEN 4          WHEN   (A.enabled=0) THEN 3     ELSE apply_status   END status FROM     tm_vinterface A     LEFT JOIN th_interface_apply_history B ON A.id = B.interface_id     AND B.account_id = 1047     AND B.enabled = 1

　　

2、单个字段的判断，case 接固定字段，按照值处理

　　

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SELECT     A.id,NAME,description,     CASE apply_status          WHEN   0 THEN "申请中"          WHEN   1 THEN  "通过"     ELSE "驳回"   END status FROM     tm_vinterface A     LEFT JOIN th_interface_apply_history B ON A.id = B.interface_id     AND B.account_id = 1047     AND B.enabled = 1