Question

I have this table: I want to search by UID

ID | VID | UID
1  |  1  | 5
1  |  1  | 6
1  |  2  | 6
2  |  3  | 5
2  |  3  | 6
2  |  4  | 6

I want to end up with this result:

ID | VID | UID
1  |  2  | 6
2  |  4  | 6

In other words, only select the entries where the VID is MAX of the UID but keeping in min NID could differ. Something like this I suppose:

select * from TABLE where uid = 6 and max(vid)

???

But this doesn’t work?

Answer 1

One way is to order by the value in descending order (so the max is at the top), then just select the first result.

SELECT t.ID,
       t.VID,
       t.UID 
FROM table t 
WHERE t.ID = 1 
ORDER BY t.VID DESC 
LIMIT 1

Or do you mean you want all rows where t.VID is the highest value? In which case you could do something like this,

SELECT t.ID,
       t.VID,
       t.UID
FROM table t
WHERE t.ID = 1
      AND t.VID = (SELECT MAX(VID) FROM table);

EDIT: Based on the edit to your question, it looks like you just want the max VID value for each ID? If I’m understanding you correctly, then this should give you what you need.

SELECT t.ID,
       max(t.VID) as VID,
       t.UID 
FROM table t 
WHERE t.UID = 6 
GROUP BY t.ID