Question

Which of the following database operations uses the ExecuteScalar method?

A. Insert a column.
B. Delete a column.
C.Update a column.
D.Count the appearances of a value in a column.

Answer 1

The ExecuteScalar method is used to count the appearances of a value in a column in a database. The correct answer is D.Count the appearances of a value in a column.

Step-by-step explanation:

The correct answer is D. Count the appearances of a value in a column. The ExecuteScalar method in database operations is used to retrieve a single value from a database.

It is commonly used in situations where you want to retrieve aggregate information, such as counting the number of times a specific value appears in a column. For example, you could use the ExecuteScalar method to count how many students have a specific grade in a student database.

The ExecuteScalar method is used when a query returns a single value. This is commonly the case when performing an aggregate operation such as counting. Of the options provided, the one that fits this description is 'D. Count the appearances of a value in a column.'

This method would typically be used in conjunction with a SELECT COUNT() query which returns a single numerical value representing the count of entries that match a certain criterion in a database column.