Implement multiple COUNT() in a single MySQL query

For this, use CASE statement. Let us first create a table −

mysql> create table DemoTable    -> (    -> LastName varchar(100)    -> ); Query OK, 0 rows affected (0.60 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable values('Smith'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Brown'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Brown'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Smith'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('Taylor'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('Taylor'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('Miller'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('Miller'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('Miller'); Query OK, 1 row affected (0.12 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable;

Output

This will produce the following output −

+----------+ | LastName | +----------+ | Smith | | Brown | | Brown | | Smith | | Taylor | | Taylor | | Miller | | Miller | | Miller | +----------+ 9 rows in set (0.00 sec)

Following is the query to implement multiple COUNT() methods in one query −

mysql> select COUNT(CASE WHEN LastName='Smith' THEN 1 END) AS TotalFrequency, -> COUNT(CASE WHEN LastName='Brown' THEN 1 END) AS TotalFrequency, -> COUNT(CASE WHEN LastName='Taylor' THEN 1 END) AS TotalFrequency, -> COUNT(CASE WHEN LastName='Miller' THEN 1 END) AS TotalFrequency -> from DemoTable;

Output

This will produce the following output −

+----------------+----------------+----------------+----------------+ | TotalFrequency | TotalFrequency | TotalFrequency | TotalFrequency | +----------------+----------------+----------------+----------------+ | 2              | 2              | 2 | 3 | +----------------+----------------+----------------+----------------+ 1 row in set (0.00 sec)