修改 MySQL 语句以允许更新

Question

如何用更新语句修改它？想要使用此语句

返回的所有记录更新“mdl_user”table中的字段“email”，值为“users@domain.com”

SELECT DISTINCT u.id AS userid, c.id AS courseid
FROM mdl_user u
    JOIN mdl_user_enrolments ue ON ue.userid = u.id
    JOIN mdl_enrol e ON e.id = ue.enrolid
    JOIN mdl_role_assignments ra ON ra.userid = u.id
    JOIN mdl_context ct ON ct.id = ra.contextid
        AND ct.contextlevel =50
    JOIN mdl_course c ON c.id = ct.instanceid
        AND e.courseid = c.id
    JOIN mdl_role r ON r.id = ra.roleid
        AND r.shortname =  'student'
WHERE e.status =0
AND u.suspended =0
AND u.deleted =0
AND ue.status =0
AND courseid =1538

Answer 1

这将更新所有选定的用户：

UPDATE mdl_user 
JOIN (
SELECT DISTINCT u.id AS userid, c.id AS courseid
FROM mdl_user u
    JOIN mdl_user_enrolments ue ON ue.userid = u.id
    JOIN mdl_enrol e ON e.id = ue.enrolid
    JOIN mdl_role_assignments ra ON ra.userid = u.id
    JOIN mdl_context ct ON ct.id = ra.contextid
        AND ct.contextlevel =50
    JOIN mdl_course c ON c.id = ct.instanceid
        AND e.courseid = c.id
    JOIN mdl_role r ON r.id = ra.roleid
        AND r.shortname =  'student'
WHERE e.status =0
AND u.suspended =0
AND u.deleted =0
AND ue.status =0
AND courseid =1538
) AS a
ON a.userid = mdl_user.id
SET email = 'users@domain.com'

修改 MySQL 语句以允许更新

Modify MySQL statement to allow update

mysql

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