我想通过将它们与我的[[cases表中的usrID和res_usrID字段进行匹配以从users表中使用 usrGivenName字段。我想在同一行上查看它们。我该怎么办?
SELECT
caseID
,c.date_created
,c.date_approval_request
,c.date_closed
,u.usrGivenName
,c.muh_usrID
FROM cases AS c
JOIN users AS u ON c.usrID=u.usrID
SELECT
caseID
,c.date_created
,c.date_approval_request
,c.date_closed
,coalesce(u.usrGivenName, ru.usrGivenName, 'Not Available')
,c.muh_usrID
FROM cases AS c
left JOIN users AS u ON c.usrID = u.usrID
left JOIN users AS ru ON c.res_usrID = ru.usrID
没有测试,但是您会明白的。
SELECT
c.caseID
, c.date_created
, c.date_approval_request
, c.date_closed
, u1.usrGivenName as user_name
, c.muh_usrID
, u2.usrGivenName as res_user_name
FROM cases AS c
JOIN users AS u1 ON c.usrID = u.usrID
JOIN users AS u2 ON c.res_usrID = u.usrID