COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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COUNT()
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LEN()
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CASE()
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NOW()
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Detailed explanation-1: -An aggregate function in SQL performs a calculation on multiple values and returns a single value. SQL provides many aggregate functions that include avg, count, sum, min, max, etc. An aggregate function ignores NULL values when it performs the calculation, except for the count function.
Detailed explanation-2: -The COUNT() aggregate function returns the total number of rows that match the specified criteria. For instance, to find the total number of employees who have less than 5 years of experience, the given query can be used. Note: A column name of the table can also be used instead of * .
Detailed explanation-3: -The following are the most commonly used SQL aggregate functions: AVG – calculates the average of a set of values. COUNT – counts rows in a specified table or view. MIN – gets the minimum value in a set of values.
Detailed explanation-4: -COUNT()-Returns the number of rows.
Detailed explanation-5: -Expert-Verified Answer According to SQL, round isn’t an aggregate function.