>Thanks for reply, but sys(2007) doesn't gives unique number for two different string, but Hash() function of java gives one unique number for a particular string. do you have any idea in sys(2007) what must be string length limit of parrameter string?
Unless you use the string itself - or a string of the same length - there is no guarantee that any function, whether it is called hash or whatever, will produce unique results. This is mathematically impossible. The only thing you can do, if the resulting string is large enough, is reduce the probability of having two identical results, until the probability is zero for practical reasons.
Hilmar.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)