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Subquery selecting over a select

I have a table users structured as follow:

userUID (int), userName (varchar), userImage (varchar)

And a table 'posts' structured as follow

postPID (int), postUID (int), postMessage (char)

Now, the postUID correspond to the author UID. When i SELECT the posts, i'd like to also select the userName and userImage field corresponding to the 开发者_JAVA百科postUID.

How could i do that?


SELECT  p.*, u.userName, u.userImage
FROM    users u
JOIN    posts p
ON      p.postUID = u.userUID


Select 
  p.postPID,
  p.postUID,
  p.postMessage,
  u.userName,
  u.userImage
From posts p
  Join users u
    On p.postUID = u.userUID

It's better to name your columns instead of selecting * as has been discussed on here in numerous threads.


It depends on how many records are returned. If not sure it is good to have top 10 or top 100 so that it only returns that many rows.

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