Hi i know this answer it was syntax wrong but i put 1 as wrong anwer.

because i thought that there may wrong with script.I know that this script will give sytax error.But i thought that there is some print mistake.

then i correct it to.

Alter table mytable with check Add constraint[checkmainvalue] check(([mainvalue])> (0))

then executed.this gives me 1 as result.because the conditon satisfied for 1 only.

This question is not difficulty.it divorsed me to put wrong anwer.There is nothing new learn from this question.