PostgreSQL find duplicate field

Question

I have table like:

ID PERSON UPDATE
1   132  1.1.2015
1   132  2.1.2015
3   152  4.5.2013
9   152  1.2.2013

I need to count persons which have different id's which is greater than 1.

If this table had a row 9 152 1.2.2014, would the result still be 2 or would it be 3? — jpmc26
– jpmc26, Commented Jan 20, 2017 at 13:26

Gordon Linoff · Accepted Answer · 2017-01-20 13:28:02Z

1

I think you want this:

select person, count(distinct id)
from t
group by person
having count(distinct id) > 1;

answered Jan 20, 2017 at 13:28

Gordon Linoff

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2 Comments

Needs to filter out id = 1.

@jpmc26 . . . Although perhaps not immediately obvious, the OP is trying to say "I need to count persons that have different ids".

Miknash · Accepted Answer · 2017-01-20 17:18:22Z

0

select person, count(*) from table
where id>1
group by person

or

select person, count(*) from table
where id<>1
group by person

Miknash

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answered Jan 20, 2017 at 13:17

starko

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