Konstantin Knizhnik writes:
> On 04/12/2024 9:03 am, Tom Lane wrote:
>> Konstantin Knizhnik writes:
>>> postgres=# create table t(x integer unique);
>>> CREATE TABLE
>>> postgres=# insert into t values (null),(null);
>>> INSERT 0 2
>>> postgres=# select count(distinct x) from t;
>>> count
>>>
On Tuesday, December 3, 2024, Konstantin Knizhnik
wrote:
>
> Is it only me who consider that current behavior of array_agg(distinct)
> contradicts to interpretation of nulls in other cases ("null" is something
> like "unknown" which means that we can not say weather two nulls are the
> same or not
On 04/12/2024 9:03 am, Tom Lane wrote:
Konstantin Knizhnik writes:
postgres=# create table t(x integer unique);
CREATE TABLE
postgres=# insert into t values (null),(null);
INSERT 0 2
postgres=# select count(distinct x) from t;
count
---
0
(1 row)
postgres=# select array_agg(dist
Konstantin Knizhnik writes:
> postgres=# create table t(x integer unique);
> CREATE TABLE
> postgres=# insert into t values (null),(null);
> INSERT 0 2
> postgres=# select count(distinct x) from t;
> count
> ---
> 0
> (1 row)
> postgres=# select array_agg(distinct x) from t;
> array
Hi hackers!
Is it only me who consider that current behavior of array_agg(distinct)
contradicts to interpretation of nulls in other cases ("null" is
something like "unknown" which means that we can not say weather two
nulls are the same or not). This is why it is allowed to insert multiple
n
