Autonumberhash128

[brindlogcool]

Hi,

i am trying to use Autonumberhash128 to reduce the field space which is the combination of character&number . Intially the size of the Key field was 1gb and after using the autonumberhash128 is almost the same i couldnt see the change in the size of the field.

[rwunderlich]

If the keys are created in the same script run (meaning not stored in a qvd) then use

autonumber(character & '|' & number)

or

autonumberHash128(character,number)

Either of those will generate sequential integer keys which will be much smaller. Both should give you the same result.

-Rob

http://robwunderlich.com

[brindlogcool]

Thanks Rob,

Can you explain in more detail what you refer meaning not stored in QVD.

[rwunderlich]

What I should have said is not being stored in a QVD that is later updated by an incremental load. If you are generating the complete set of keys every run then it's fine to store them in a QVD.

If you are updating only some rows in the QVD using incremental load, then storing the keys would give incorrect results. The update rows would begin autonumbering from 1 again and you would have duplicate keys. If you are not doing incremental loads, no worries.

-Rob

[brindlogcool]

Thanks it was really useful.

[brindlogcool]

Hi Rob,

  I was testing the Autonumber & Autonumberhash128 for a field which is combination of specical character,String and number, Where the Autonumber is working fine, but the Autonumberhash128 is not working as it should.

The first record (Serial number 1) is not having any values in the Autohashnumber128. I am not sure why the Autonumberhash128 is start with the blank record .I am not sure where i am missing .

This is how it looks

ColumnA    ActualColumn   GeneratedKey(Autonumberhash128)

      -                    -                        1

     123       Test|123                      2

But i didnt see the blank record in the Autonumber.  

Another issue popped up,i have generated a key using Automber and stored in a QVD. Genereated one more QVD with Automber and trying to Compare with previous one. I am validating the resutls to find anythings i have missed. Mean time i would like to know any other restrictions other than Incremental reload.

[brindlogcool]

Hi Rob,

Issue is resolved and the Autonumber or Autohashnumber will not be solution for my problem. Thanks for your responses

[#8]

Hi,

Does anyone know how can i autonumber with condition. meaning, i want it to recount at the condition i set eg, in the if statement.

for the moment, it keeps the number continuously.

thanks.

[rwunderlich]

Use the second param of autonumber. If this is a new value, the numbering starts over.

-Rob