database - Counting columns null and not null in PostgreSql -

i need count columns has null values , not null values each row, don't have idea of how can in postgresql.

you need specify column name in count(), skip null:s

select avg(c),count(c) (select generate_series(1,10) union select null) a(c); 

ignore stuff after from, it's return list of values

to make more clear:

select   avg(c),   count(c) count_column,   count(*) count_star,   sum(c),   array_agg(c) (   select generate_series(1,10) union select null order 1 ) a(c);          avg         | count_column | count_star | sum |          array_agg           --------------------+--------------+------------+-----+-----------------------------  5.5000000000000000 |           10 |         11 |  55 | {1,2,3,4,5,6,7,8,9,10,null} (1 row)