Group concatenate the last name from a MySQL column and set a condition to display limited records

Use GROUP_CONCAT() to perform group concatenation and set a condition. Let us first create a table −

mysql> create table DemoTable813(
   UserId int NOT NULL AUTO_INCREMENT PRIMARY KEY,
   UserFirstName varchar(100),
   UserLastName varchar(100)
);
Query OK, 0 rows affected (0.49 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable813(UserFirstName,UserLastName) values('Adam','Smith');
Query OK, 1 row affected (0.17 sec)
mysql> insert into DemoTable813(UserFirstName,UserLastName) values('Chris','Brown');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable813(UserFirstName,UserLastName) values('David','Miller');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable813(UserFirstName,UserLastName) values('Carol','Taylor');
Query OK, 1 row affected (0.22 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable813;

This will produce the following output −

+--------+---------------+--------------+
| UserId | UserFirstName | UserLastName |
+--------+---------------+--------------+
|      1 | Adam          | Smith        |
|      2 | Chris         | Brown        |
|      3 | David         | Miller       |
|      4 | Carol         | Taylor       |
+--------+---------------+--------------+
4 rows in set (0.00 sec)

Following is how to group concatenate and display only the last names −

mysql> select group_concat(UserLastName) from DemoTable813 where UserId < 4;

This will produce the following output −

+----------------------------+
| group_concat(UserLastName) |
+----------------------------+
| Smith,Brown,Miller         |
+----------------------------+
1 row in set (0.00 sec)