Let us first create a table −
mysql> create table DemoTable1898 ( Number int ); Query OK, 0 rows affected (0.00 sec)
Insert some records in the table using insert command −
mysql> insert into DemoTable1898 values(10); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1898 values(70); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1898 values(30); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1898 values(50); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1898 values(40); Query OK, 1 row affected (0.00 sec)
Display all records from the table using select statement −
mysql> select * from DemoTable1898;
This will produce the following output −
+--------+ | Number | +--------+ | 10 | | 70 | | 30 | | 50 | | 40 | +--------+ 5 rows in set (0.00 sec)
Here is the query to perform ORDER BY with numeric user-defined variable −
mysql> set @limitValue:=1; Query OK, 0 rows affected (0.00 sec) mysql> set @query:=CONCAT('select * from DemoTable1898 order by ',@limitValue); Query OK, 0 rows affected (0.00 sec) mysql> prepare stmt from @query; Query OK, 0 rows affected (0.00 sec) Statement prepared mysql> execute stmt;
This will produce the following output −
+--------+ | Number | +--------+ | 10 | | 30 | | 40 | | 50 | | 70 | +--------+ 5 rows in set (0.00 sec)
Here is the query to deallocate the prepare query −
mysql> deallocate prepare stmt; Query OK, 0 rows affected (0.00 sec)