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Mastering the COUNT() Aggregate Function in SQL: A Comprehensive Guide

Rumman Ansari Software Engineer 2024-07-19 02:08:58 5976 Share
Subject Syllabus Details Subject Details

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Table of Content:

The COUNT() function returns the number of rows that matches a specified criteria.

The AVG() function returns the average value of a numeric column.

The SUM() function returns the total sum of a numeric column.

Syntax:


SELECT COUNT(column_name)
FROM table_name
WHERE condition;

We will apply COUNT function in this below table:

We will find the how may employee are available

EmpId	EmpName	EmpAddress	EmpSalary	EmpDept
11	Rambo	Kolkata	30000	ADMIN
21	Inza	Bihar	31000	SALES
32	Samser	Kolkata	32000	IT
41	Kamran	Hydrabad	33000	ITIS
52	Azam	Kolkata	33000	ITIS

Example: COUNT

Code:


SELECT COUNT(EmpId) AS NoOfEmployee FROM EmployeeDetails

Output:

The above code will produce the following result-


NoOfEmployee
5