Postgresql 如何找到不同的值并计数

Question

I have a table with ID, data 1, and few other columns... data 1 has NA as well.

I need to find a distinct ID, followed by the total count of each ID and the count for each ID whose data has NA. I need to determine how much of NA values are loaded for each ID.

Thanks Sai

Answer 1

select 
  id,
  count(*) as total_count,
  count(*) filter (where data1 = 'NA') as na_count
from _table 
group by id;

Answer 2

You can use standard sql with conditional aggregation as follows:

Select id, count(1) as total,
       Count(case when data1='NA' then 1 end) as NA_count
  From your_table
Group by id;