I like to use the result from another query to address the column name. For this I like to use `CONCAT()`. But somehow it don't work; when I run this line I get 0 rows back:

`SELECT * FROM cover WHERE CONCAT('c','9') = 1;`

When I don't make use of `CONCAT()` it work perfectly:

`SELECT * FROM cover WHERE c9 = 1;`

And also `CONCAT()` seems to work. With this I get a result:

`SELECT CONCAT('c','9');`

I tried all solution from this question:
[MySQL select with CONCAT condition](https://stackoverflow.com/questions/5734570/mysql-select-with-concat-condition)

like this one, but i always got 0rows back:

```
SELECT * FROM (
  SELECT id, CONCAT('c', '9') as target 
  FROM cover) base 
WHERE target = "1"

```

My MySQL Version is; 10.1.16-MariaDB