The table has 3 columns 4 rows. The output is which column has least null values

The table has 3 columns 4 rows. The output is which column has least null values( A COL SHOULD BE THE OUTPUT)
Write the query plz.

A B C
================
1 NULL 2
NULL 3 4
NULL 5 6
7 NULL NULL

O/P

C
=
2
4
6

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The table has 3 columns 4 rows. The output is which column has least null values( A COL SHOULD BE TH..

Answer / rameshganesan

Select (Case
When a = Least Then (select 'A'||CHR(10)||'='||CHR(10)||ListAgg(a,CHR(10)) Within Group(order by a) from Least_Col)
When b =Least Then (select 'B'||CHR(10)||'='||CHR(10)||ListAgg(b,CHR(10)) Within Group(order by b) from Least_Col)
Else (select 'C'||CHR(10)|| '='||CHR(10)||ListAgg(c,CHR(10)) Within Group(order by c) from Least_Col) end)ab
From (Select count(a) a,count(b) b,count(c) c,greatest(count(a),count(b),count(c)) Least From Least_Col);

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1 Yes

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The table has 3 columns 4 rows. The output is which column has least null values( A COL SHOULD BE TH..

Answer / ravi gali

select c from tablename
where c IS NOT NULL;

Is This Answer Correct ?

2 Yes

4 No

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