MySQL query to group by names and display the count in a new column


Use GROUP BY with the COUNT() method. Group the names with GROUP BY and count using the COUNT() method. Let us first create a table −

mysql> create table DemoTable
(
   Name varchar(30)
);
Query OK, 0 rows affected (0.63 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable values('Chris');
Query OK, 1 row affected (0.15 sec)
mysql> insert into DemoTable values('Robert');
Query OK, 1 row affected (0.11 sec)
mysql> insert into DemoTable values('Mike');
Query OK, 1 row affected (0.10 sec)
mysql> insert into DemoTable values('Robert');
Query OK, 1 row affected (0.07 sec)
mysql> insert into DemoTable values('Mike');
Query OK, 1 row affected (0.09 sec)
mysql> insert into DemoTable values('David');
Query OK, 1 row affected (0.12 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable;

This will produce the following output −

+--------+
| Name   |
+--------+
| Chris  |
| Robert |
| Mike   |
| Robert |
| Mike   |
| David  |
+--------+
6 rows in set (0.00 sec)

Following is the query to group by names and display the count −

mysql> select Name,count(Name) as NumberOfRowsPerName from DemoTable group by Name;

This will produce the following output −

+--------+---------------------+
| Name   | NumberOfRowsPerName |
+--------+---------------------+
| Chris  |                   1 |
| Robert |                   2 |
| Mike   |                   2 |
| David  |                   1 |
+--------+---------------------+
4 rows in set (0.00 sec)
raja
Published on 09-Oct-2019 14:01:55
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