Concatenate some of the column values in a single line with MySQL and prefix a particular string “MR.” to every string

The CONCAT() method would be used to concatenate “MR” to every string, whereas GROUP_CONCAT() to concatenate some of the column values in a single line.

Let us first see an example and create a table −

mysql> create table DemoTable799(
   UserId int,
   UserName varchar(100),
   UserAge int
);
Query OK, 0 rows affected (0.56 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable799 values(101,'John',21);
Query OK, 1 row affected (0.18 sec)
mysql> insert into DemoTable799 values(102,'Chris',26);
Query OK, 1 row affected (0.22 sec)
mysql> insert into DemoTable799 values(101,'Robert',23);
Query OK, 1 row affected (0.15 sec)
mysql> insert into DemoTable799 values(103,'David',24);
Query OK, 1 row affected (0.10 sec)
mysql> insert into DemoTable799 values(101,'Mike',29);
Query OK, 1 row affected (0.18 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable799;

This will produce the following output −

+--------+----------+---------+
| UserId | UserName | UserAge |
+--------+----------+---------+
| 101    | John    | 21       |
| 102    | Chris   | 26       |
| 101    | Robert  | 23       |
| 103    | David   | 24       |
| 101    | Mike    | 29       |
+--------+----------+---------+
5 rows in set (0.00 sec)

Here is the query to concatenate strings −

mysql> select UserId,GROUP_CONCAT(CONCAT('MR.', UserName)) from DemoTable799 group by UserId;

This will produce the following output −

+--------+---------------------------------------+
| UserId | GROUP_CONCAT(CONCAT('MR.', UserName)) |
+--------+---------------------------------------+
| 101    | MR.John,MR.Robert,MR.Mike             |
| 102    | MR.Chris                              |
| 103    | MR.David                              |
+--------+---------------------------------------+
3 rows in set (0.00 sec)