Question

Below it the table which contains Actual Count and Error Count for each ID.

USER_ID    |    Actual_Count    |   Error_Count
-----------+--------------------+---------------------
1345653         5                     4
534140349       5                     0
682527813       4                     0
687612723       3                     0
704318001       5                     4

So if you look at the above scenario, For this 1345653 ID Out of 5, it has 4 errors, same with 704318001 ID, out of 5 it has 4 errors. And all other ID’s they didn’t have any errors as Error_Count is Zero for them. How can I calculate the total error percentage in SQL? Is it possible to calculate the total error percentage?

Answer 1

You can simply sum and divide the individual counts:

SELECT 100 * sum(Error_Count) / sum(Actual_Count) FROM MyTable;

This will not work in all databases, because some (such as SQL Server) do integer division. The following does work:

SELECT 100 * sum(Error_Count*1.0) / sum(Actual_Count) FROM MyTable;