sqlnullgroup-by

How do I return my records grouped by NULL and NOT NULL?

I have a table that has a processed_timestamp column -- if a record has been processed then that field contains the datetime it was processed, otherwise it is null.

I want to write a query that returns two rows:

NULL        xx -- count of records with null timestamps
NOT NULL    yy -- count of records with non-null timestamps

Is that possible?

Update: The table is quite large, so efficiency is important. I could just run two queries to calculate each total separately, but I want to avoid hitting the table twice if I can avoid it.

Solution

  • Oracle:

    group by nvl2(field, 'NOT NULL', 'NULL')