Question

I’m trying to enumerate the groups inside a certain view.

Example, from this view:

ID      FK1     FK2 FK3 FK4
104091  10160   1   1   29152
106797  10161   2   1   NULL
34682   10162   1   6   28556
61582   10162   1   6   28557
53045   10163   1   1   29154
23918   10164   1   6   28731
34683   10164   1   6   28729
89003   10164   1   4   28728
50547   10164   1   4   28727
50548   10165   1   6   29846
34684   10165   1   5   29847
23919   10165   1   5   29844

I’d like to have something like:

ID      FK1     FK2 FK3 FK4     C
104091  10160   1   1   29152   1
106797  10161   2   1   NULL    2
34682   10162   1   6   28556   3
61582   10162   1   6   28557   3
53045   10162   1   1   29154   4
23918   10164   1   6   28731   5
34683   10164   1   6   28729   5
89003   10164   1   4   28728   6
50547   10164   1   4   28727   6
50548   10165   1   6   29846   7
34684   10165   1   5   29847   8
23919   10165   1   5   29844   8

As you can see, it looks like a

ROW_NUMBER() OVER (PARTITION BY FK1, FK2, FK3 ORDER BY FK1, FK2, FK3) AS C

With the only difference that PARTITION BY resets the row_number for each group. Instead, I’d like to have a unique number for each group. More like a GROUP_NUMBER()

I hope the question was clear enough 🙂

Answer 1

DENSE_RANK() OVER (ORDER BY FK1, FK2, FK3) AS C

Should do what you need.