topic one point difference? in QlikView

one point difference?

Fri, 14 Nov 2014 03:12:01 GMT

i need minimum one difference between

autonumbe ,autonumberhash128, autonumberhash256

Re: one point difference?

SergeyMak — Fri, 14 Nov 2014 03:31:31 GMT

with Autonumber you can use only one field or concatenation of the fields like and you can use the name of this autonum

Autonumber (Field, 'Name1') or Autonumber(Field1&Field2, 'Name2')

with autonumberhash128, autonumberhash256

you can use several field

Autonumber128(Field1,Field2)

Sergey

Re: one point difference?

jagan — Fri, 14 Nov 2014 04:13:56 GMT

Hi Manoj,

The characters or bytes is the difference between the various has functions,

Hash functions in QlikView

In QlikView, the following hash functions are available:

autonumberhash128(): a 128 bit hash function that returns a 22 character string.

autonumberhash256(): a 256 bit hash function that returns a 43 character string.

The number of bits determines the output range of the function. A 128 bit hash can store 2^128 (or, 340.282.366.920.938.000.000.000.000.000.000.000.000) different combinations. 160 and 256 bit can store even more combinations (2^160 and 2^256 respectively).

Besides these functions, QlikView also has the AutoNumberHash128() and AutoNumberHash256()functions. These functions basically take the output of the Hash128() and Hash256() function and passes it through the AutoNumber() function. While I think they have a nicer syntax than the regularAutoNumber(), you can supply a comma-separated list of fields instead of a concatenated string, the usefulness of these functions eludes me.

Hope this helps you.

Regadrs,

Jagan.

Re: one point difference?

jagan — Fri, 14 Nov 2014 04:14:33 GMT

Hi,

Check this link hope it helps you in understanding better

qlikfix.com/2014/03/11/hash-functions-collisions/

Regards,

jagan.

Re: one point difference?

jagan — Fri, 14 Nov 2014 04:18:06 GMT

Hi,

Check this links to

hash128(), hash160 & hash256 ?

Regards,

Jagan.