Can Count(*) ever return null?

Question

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Does COUNT(*) always return a result?

Is it possible in any scenario for the Count() function to return NULL?

Discussed previously [Does COUNT(*) always return a result?](http://stackoverflow.com/questions/2552086/does-count-always-return-a-result). never NULL: zero or no result at all — gbn, Feb 11 '11 at 15:23
Here's an interesting related [question](http://stackoverflow.com/questions/4115710/count-returns-null) — rosscj2533, Feb 11 '11 at 15:35

Simon · Accepted Answer · 2012-05-09T07:44:49.647

25

No, it will only return a zero (or non-zero) result. SqlServer will not return null.

edited May 09 '12 at 07:44

answered Feb 11 '11 at 14:50

Simon

Surely you mean "or non-zero and non-null"?? – RichardTheKiwi Feb 12 '11 at 22:04
@cyberwiki - good point :-) Would be quite pointless if it always returned zero! – Simon Feb 14 '11 at 11:01
2

There are some cases where there is no result returned (if your select has a `GROUP BY` and there is no group). Depending on how you use your query, for instance if you use some ORM, this no result might be mapped to a `null`. – kord Jun 03 '20 at 21:16

score 7 · Answer 2 · answered Feb 11 '11 at 14:51

7

According to the MSDN page, no.

That said:

For return values greater than 2^31-1, COUNT produces an error. Use COUNT_BIG instead.

answered Feb 11 '11 at 14:51

Matt Ball

score 4 · Answer 3 · answered Feb 11 '11 at 14:52

4

No.

This will be 0

select count(*)
where 0=1

This will be 1

select count(*)

answered Feb 11 '11 at 14:52

Mikael Eriksson

score 2 · Answer 4 · answered Feb 11 '11 at 14:54

2

No it returns a zero if the table does not have any records in the table

answered Feb 11 '11 at 14:54

Pinu

score 1 · Answer 5 · answered Feb 11 '11 at 14:53

1

No. If the table or specific field being counted are empty it will return zero.

answered Feb 11 '11 at 14:53

HLGEM

5 Answers5