In SQL, the aggregate function which will display the cardinality of the table is \(\_\_\_\_\_\).
In SQL, the aggregate function which will display the cardinality of the table is \(\_\_\_\_\_\).
Show Hint
Use count(*) when you need to determine the total number of rows in a table, regardless of whether they contain NULL values or not.
sum()
count(*)
avg()
sum(*)
The Correct Option is B
Solution and Explanation
In SQL, the count(*) function is used to count the number of rows in a table, which effectively gives the cardinality of the table. Other functions like sum() and avg() are used for numerical aggregations, not for counting rows.
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