How to add a column from a select query but the value from the new column will be the row count of the MySQL select query?

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

mysql> create table DemoTable1342    -> (    -> Score int    -> ); Query OK, 0 rows affected (0.68 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable1342 values(80); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable1342 values(98); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable1342 values(78); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable1342 values(89); Query OK, 1 row affected (0.07 sec)

Display all records from the table using select statement −

mysql> select * from DemoTable1342;

This will produce the following output −

+-------+ | Score | +-------+ |    80 | |    98 | |    78 | |    89 | +-------+ 4 rows in set (0.00 sec)

Following is the query to add a column from a select query but the value from the new column will be the row count of the MySQL select query −

mysql> select Score,row_number() over() as `Rank` from DemoTable1342 order by Score DESC;

This will produce the following output −

+-------+------+ | Score | Rank | +-------+------+ |    98 |    1 | |    89 |    2 | |    80 |    3 | |    78 |    4 | +-------+------+ 4 rows in set (0.32 sec)