id tip1 tip2 valoare
15 1 1 23,5
17 1 1 24,5
18 1 1 25
13 2 1 26
14 1 2 27
I have to delete from this table, all the rows that have the same value on (tip1 and tip2), leaving one row. All this with only one delete.
In the example, after the delete query, rows with 17, 18 will...