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)
Published on 05-Nov-2019 12:00:01
