MySQL Count

This example illustrates how to use count() in MySQL database.


 
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MySQL Count

     

This example illustrates how to use count() in MySQL database.

Count(): The Count() is an aggregate function that counts all the rows in a specified table. It returns a numeric value. If you use COUNT(*) that counts the number of rows.

 

 

 

 

Table: employee

CREATE TABLE `employee` ( 
`emp_id` int(11) NOT NULL auto_increment, 
`emp_name` varchar(10) character set utf8 NOT NULL, 
`emp_salary` int(11) NOT NULL, 
`emp_startDate` datetime NOT NULL, 
`dep_name` varchar(50) NOT NULL, 
PRIMARY KEY (`emp_id`) 
)

To select all records use the query: 

SELECT * FROM employee;

Output:

To use COUNT(*) with the sql query:

SELECT COUNT(*) FROM employee;

Output:

To use COUNT(column_name) with the GROUP BY sql query:

You can use count function on column. If it is used with group by clause then it counts all the items that are in a group. For example, the query below shows the department name and total no of employee in the department with the help of count function.

SELECT dep_name,COUNT(emp_name) As Total FROM employee GROUP BY (dep_name);

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MySQL Count

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