why we give in query sql 1=0

Question

I have seen in some programmers use 1=0 in where condition for select query , why they use this condition.

Answer 1

in sql server, you can quickly create a copy of a table without any data like this

select * into Newtable
from Oldtable
where 1 = 0

this will create a new table with the same structure as the old table

Another option is to return an empty resultset

Answer 2

The only possible use for that would be to prevent the query from returning any rows. I've done it occasionally for testing "no results found" type logic.