复杂的sql语句join的使用(left join,right join)_MySQL
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2022-05-24 16:04:50
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SELECT u.*,count(u.id) AS sum
02
FROM user AS u
03
LEFT JOIN post AS p
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ON p.user_id = u.id
05
RIGHT JOIN user_has_group as up
06
ON up.user_id = u.id
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RIGHT JOIN user_has_email as ue
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ON ue.user_id = u.id
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WHERE u.username != ''
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AND up.group_id = {$args['groupid']}
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AND ue.email = '{$args['useremail']}'
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GROUP BY u.id ORDER BY u.id desc bitsCN.com
02
FROM user AS u
03
LEFT JOIN post AS p
04
ON p.user_id = u.id
05
RIGHT JOIN user_has_group as up
06
ON up.user_id = u.id
07
RIGHT JOIN user_has_email as ue
08
ON ue.user_id = u.id
09
WHERE u.username != ''
10
AND up.group_id = {$args['groupid']}
11
AND ue.email = '{$args['useremail']}'
12
GROUP BY u.id ORDER BY u.id desc bitsCN.com
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