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.
Top CBSE CLASS XII Computer Science Questions
- State True or False:
While defining a function in Python, the positional parameters in the function header must always be written after the default parameters. The SELECT statement when combined with \(\_\_\_\_\_\_\) clause, returns records without repetition.
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The SELECT statement when combined with \(\_\_\_\_\_\_\) clause, returns records without repetition.
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Assertion (A): CSV file is a human-readable text file where each line has a number of fields, separated by a comma or some other delimiter.
Reason (R): writerow() method is used to write a single row in a CSV file.
Mark the correct choice:
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