Information on Ranges and select-options

Hi All,

A very basic information required.Can any one tell me if we give a range in an condition comparing a internal table field with the range value and if the case is internal table field ia a numeric value but range is empty in such case why the control is going inside the condition.

Can any one tell me why does range behave in this way.

thanks in anticipation.

Regards,

Rajashree