How to update in PHP MYSql

Question

I want to update data. my table is.

ID Name Cat Points
1 John trainee 55
2 Ram manager 75
3 Shiva manager 80
4 Mark trainee 45
5 Mary intern 38
6 Tom trainee 60

from the above table i want to update only trainee in the cat field as 0. how to make it.

i know how to use all cat fields to zero.

$sql="UPDATE $tbl_name SET `cat` = '0'";

the result should be like below.

ID Name Cat Points
1 John trainee 0
2 Ram manager 75
3 Shiva manager 80
4 Mark trainee 0
5 Mary intern 38
6 Tom trainee 0

Answer 1

$sql="UPDATE $tbl_name SET Points = 0 WHERE Cat = 'trainee'";

Answer 2

Try this query:

$sql = 'UPDATE $tbl_name SET Points = 0 WHERE Cat = "trainee"';