Oh, sir Cetin thanks, your codes work fine, I need some guidelines

I want want to validata sno+code then what will be the changes in your codes

select count(*) from subjects where sno=this.value and recno() != m.rec into array x

The grid should accept Following data
1--VB
1--VFP

and it should not accept this data
1--VB
1--VB

Validation on sno+code