MySQL query to select a random row value (Id and Name) having multiple occurrences (Name)?

For this, use RAND() for random records and LIMIT 1 to get only a single value. However, use the WHERE clause to select that particular ‘Name’, which is repeating.

Let us first create a table −

mysql> create table DemoTable
(
   Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,
   Name varchar(20)
);
Query OK, 0 rows affected (1.65 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable(Name) values('Chris');
Query OK, 1 row affected (0.19 sec)
mysql> insert into DemoTable(Name) values('Bob');
Query OK, 1 row affected (0.11 sec)
mysql> insert into DemoTable(Name) values('David');
Query OK, 1 row affected (0.22 sec)
mysql> insert into DemoTable(Name) values('Bob');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable(Name) values('Bob');
Query OK, 1 row affected (0.08 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable;

This will produce the following output −

+----+-------+
| Id | Name  |
+----+-------+
|  1 | Chris |
|  2 | Bob   |
|  3 | David |
|  4 | Bob   |
|  5 | Bob   |
+----+-------+
5 rows in set (0.65 sec)

Following is the query to fetch a random value −

mysql> select *from DemoTable where Name='Bob' order by rand() limit 1;

This will produce the following output −

+----+------+
| Id | Name |
+----+------+
| 5  | Bob  |
+----+------+
1 row in set (0.00 sec)

AmitDiwan

Published on 03-Oct-2019 06:57:39