MySQL列转行的用法:## 标题

SELECT
 a.employeeId,
 MAX( CASE checkType WHEN ‘OnDuty’ THEN userCheckTime END )OnTime,
 MAX( CASE checkType WHEN ‘OffDuty’ THEN userCheckTime END ) OffTime 
 FROM
 t_oa_check_work a
 GROUP BY
 a.employeeId,
 a.workDate