What's the most efficient way to pull data from MySQL so that it is formatted with duplicate values

MySQLMySQLi Database

For this, you can use GROUP_CONCAT(). Let us first create a table −

mysql> create table DemoTable1561
   -> (
   -> StudentName varchar(20),
   -> Title text
   -> );
Query OK, 0 rows affected (0.60 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable1561 values('Adam','Learning Java');
Query OK, 1 row affected (0.18 sec)
mysql> insert into DemoTable1561 values('Bob','Learning C');
Query OK, 1 row affected (0.11 sec)
mysql> insert into DemoTable1561 values('Adam','Learning Spring and Hibernate Framework');
Query OK, 1 row affected (0.22 sec)
mysql> insert into DemoTable1561 values('Carol','Learning MySQL from basic');
Query OK, 1 row affected (0.30 sec)

Display all records from the table using select statement −

mysql> select * from DemoTable1561;

This will produce the following output −

+-------------+-----------------------------------------+
| StudentName | Title                                   |
+-------------+-----------------------------------------+
| Adam        | Learning Java                           |
| Bob         | Learning C                              |
| Adam        | Learning Spring and Hibernare Framework |
| Carol       | Learning MySQL from basic               |
+-------------+-----------------------------------------+
4 rows in set (0.00 sec)

Here is the query to pull the data from MySQL so that it is formatted −

mysql> select StudentName,group_concat(Title separator ',') as FormattedOutput from DemoTable1561
   -> group by StudentName;

This will produce the following output −

+-------------+-------------------------------------------------------+
| StudentName | FormattedOutput                                       |
+-------------+-------------------------------------------------------+
| Adam        | Learning Java,Learning Spring and Hibernate Framework |
| Bob         | Learning C                                            |
| Carol       | Learning MySQL from basic                             |
+-------------+-------------------------------------------------------+
3 rows in set (0.00 sec)
raja
Published on 12-Dec-2019 06:46:11
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