一个mysql表中的水平looper [重复]

Question

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• MySQL pivot table 8 answers

I have a mysql table:

Each user have 4 emails:

 id user_Id email
 1  11      [e-mail]
 2  11      [e-mail]
 3  11      [e-mail]
 4  11      [e-mail]
 5  12      [e-mail]
 6  12      [e-mail]
 7  12      [e-mail]
 8  12      [e-mail]
 9  13      [e-mail]
 10 13      [e-mail]
 11 13      [e-mail]
 12 13      [e-mail]

How to sort the row result horizontally?

Like that:

 user_Id   email1           email2           email3             email4
 11        [e-mail] [e-mail] [e-mail]   [e-mail]
 12        [e-mail] [e-mail] [e-mail]   [e-mail]
 13        [e-mail] [e-mail] [e-mail]   [e-mail]

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Answer 1

select user_Id , GROUP_CONCAT(email ORDER BY email) from tab
group by user_Id