Обсуждение: number of not null arguments

Hello

this function doesn't exists, but you can you to write (min PostgreSQL 8.4)

 create or replace function notnull_count(variadic anyarray) returns
int as $$select count(x)::int from unnest($1) g(x)$$ language sql;

it working just for scalar types:

pavel=# SELECT notnull_count(1, 1, NULL, NULL); notnull_count
───────────────
             2
(1 row)

it doesn't working for arrays, but you can to little bit modify query

pavel=#  SELECT notnull_count(array_upper(ARRAY[1,2,3],1),
array_upper(ARRAY[10,20,30],1), NULL, array_upper(ARRAY[NULL],1));
 notnull_count
───────────────
             3
(1 row)

next (but general solution) is custom function in C - it can be very simple

Regards

Pavel Stehule


2010/11/26 Murat Kabilov <kabilovmf@gmail.com>:
> Hello,
> Is there a function which returns number of not null arguments?
> SELECT notnull_count(1, 1, NULL, NULL)
>  notnull_count
> ---------------
>              2
> SELECT notnull_count(ARRAY[1,2,3], ARRAY[10,20,30], NULL, ARRAY[NULL])
>  notnull_count
> ---------------
>              3
> Thanks
> --
> Murat Kabilov