If a table has a column "dept" (declared to have nulls) and
there are 10 rows in the table of which 3 have a null value
in the dept column, what will select count(*) and select
count(distinct dept) return?
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Answer Posted / madhuri tungal
select count(*) returns 10 --- this is right. But,
select count(distinct dept) returns 7. Because null values
are not considered as distinct.
| Is This Answer Correct ? | 6 Yes | 1 No |
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