sql using a case when then determines whether the field is not null effect
The CASE
columnName
the WHEN null
THEN ELSE 0 END columnName
although columnName is empty, but the result is not 0, the result should be zero fishes.
although columnName is empty, but the result is not 0, the result should be zero fishes.
Correct wording:
CASE WHEN columnName is null THEN 0 ELSE columnName END