How can create new column by query that column not in table:

How can create new column by query that column not in table:

We have one table test in this table 2 columns

Sno, name I want 3^rd columns for ues then we have create 3^rd column by query and also fixed that column value “0”.

select sno,name,'0' as amount from test

Out put:

sno	name	amount
1	cp	0
2	ram	0
3	jon	0

Understand diffrence between 1^st and 2^nd query:

select sno,name,sno as amount from test

Output:

sno	name	amount
1	cp	1
2	ram	2
3	jon	3