Sql COUNT() Function

COUNT() Function:- The COUNT() function returns the number of rows that matches specified criteria.

  • SQL COUNT(column_name) Syntax :-
The COUNT(column_name) function returns the number of values of the specified column.

           SELECT COUNT(column_name) 
           FROM table_name;

  • SQL COUNT(*) Syntax:- This function returns the number of records in a table.
            SELECT COUNT(*)
            FROM table_name;

  • SQL COUNT(DISTINCT column_name) Syntax:- This function returns the number of distinct values of the specified column.
           SELECT COUNT(DISTINCT column_name)
           FROM table_name ;

EXAMPLE:-
Consider the following CUSTOMERS table:- 

  • SQL COUNT(column_name) Example :-
          SELECT COUNT(CustomerID) As ID 
          FROM CUSTOMERS ;

OUTPUT:-

SQL COUNT(*) Example :-

SELECT COUNT(*) AS total
FROM CUSTOMERS
WHERE salary < 15000 ;

OUTPUT:-



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