On 2/1/21 4:53 PM, Matt Zagrabelny wrote:
Greetings,
Is there a preferred method of counting rows?
count(*) vs count(field_name)
I have used count(*) for a long time and am hitting an inconsistency. At
least it is an inconsistency to me (I'm sure there is an explanation)...
INCORRECT OUTPUT (not desired results)
$ select calendar.entry, count(*) from
generate_series('2020-01-01'::date, '2021-01-10'::date, '1
day'::interval) as calendar(entry) left join call_records on
calendar.entry = call_records.timestamp::date group by calendar.entry;
[...]
2020-08-30 00:00:00-05 │ 1
2020-08-31 00:00:00-05 │ 1
[...]
CORRECT OUTPUT (desired results)
$ select calendar.entry, count(id) from
generate_series('2020-01-01'::date, '2021-01-10'::date, '1
day'::interval) as calendar(entry) left join call_records on
calendar.entry = call_records.timestamp::date group by calendar.entry;
[...]
2020-08-30 00:00:00-05 │ 0
2020-08-31 00:00:00-05 │ 0
[...]
What am I missing between count(*) and count(id)?
Thanks for any help!
-m
You got one null from count(*) likely.
