Q. What is the result of following query?
Rajeev Kumar
SELECT CASE WHEN null = null THEN ‘True’ ELSE ‘False’END AS Result;
SELECT
CASE WHEN null = null
THEN ‘True’
ELSE ‘False’
END AS Result;
Ans :- Null
When we compare the null = null then sql understand it like Unknown but when we return its value in identity then you will get the null as result.
False
The result will be 'False'This is because the comparison 'NULL=NULL' evaluates to 'UNKNOWN', and since there is no specific condation for 'UNKNOWN' in your 'CASE' statement, it falls back to the 'ELSE' clause, which return 'False'