Question

Below is my table, a User could have multiple profiles in certain languages, non-English profiles have a higher priority.

 +----------+--------+----------------+----------------+ |ProfileID |UserID  |ProfileLanguage |ProfilePriority | +----------+--------+----------------+----------------+ |1         |1       |en-US           |2               | +----------+--------+----------------+----------------+ |2         |1       |es-MX           |1               | +----------+--------+----------------+----------------+ |3         |1       |ja-JP           |1               | +----------+--------+----------------+----------------+ |4         |2       |es-MX           |1               | +----------+--------+----------------+----------------+ |5         |2       |ja-JP           |2               | +----------+--------+----------------+----------------+ |6         |2       |de-DE           |1               | +----------+--------+----------------+----------------+ |7         |3       |en-US           |2               | +----------+--------+----------------+----------------+  

For example: When a Spanish-speaking visitor requests my site (where ProfileLanguage = ‘es-MX’ or ProfilePriority = 2), I want the records like below:

 +----------+--------+----------------+----------------+ |ProfileID |UserID  |ProfileLanguage |ProfilePriority | +----------+--------+----------------+----------------+ |2         |1       |es-MX           |1               | +----------+--------+----------------+----------------+ |5         |2       |ja-JP           |2               | +----------+--------+----------------+----------------+ |7         |3       |en-US           |2               | +----------+--------+----------------+----------------+  

Below, is the basic SQL to get the users:

SELECT UserID, MIN(ProfilePriority) AS ProfilePriority FROM Profile WHERE ProfileLanguage = 'es-MX' OR ProfilePriority = 2 GROUP BY UserID 

But as you know, I can only get the UserID, but I also need other column information, like ProfileID etc.. So I hope experts here could tell me the correct SQL expression to get the right records.

Answer 1

This may work, if profilepriority and userid could be a composite unique key;

select p.* from Profile p join  (SELECT UserID, MIN(ProfilePriority) AS ProfilePriority FROM Profile WHERE ProfileLanguage = 'en-US' OR ProfilePriority = 2 GROUP BY UserID) tt on p.userID = tt.UserID and p.ProfilePriority = tt.ProfilePriority