Null. Empty and Filled count in a postgresql table

I need to count how many fields are null, empty and filled in a table. Where each column would be a field, for example:

select COUNT(1),
  case when table.name is null
        then 'Null'
  when table.name = ''
        then 'Empty'
  else 'Filled' end
from table

(this is an exemple)

FIELD   NULL    EMPTY    FILLED
name     0         2       98
age     10        10       80
heigh    0        50       50

Does anyone have any idea how I can do this? This table has about 30 columns.

Answer

You can convert each row to a JSON value and then group by the keys of those json value (which are the column names):

select d.col, 
       count(*) filter (where value is null) as null_count,
       count(*) filter (where value is not null) as not_null_count,
       count(*) filter (where value = '') as empty
from the_table t
  cross join jsonb_each_text(to_jsonb(t)) as d(col, value)
group by d.col;  

Note that this is going to be much slower than manually listing every column like you did.