Join the columns having HASH values

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rohit_mca2003
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Join the columns having HASH values

Post by rohit_mca2003 »

Hi,

We have requirement to join the columns having HASH value (these hash values have been computed by checksum).

First I tried by 'hash Partition' and sort on this column (which has hash value) from both side of join but all the records do not match. But I expected all the records should be matched as data in source and target are same.

I ran stages in sequential manner as well but still I do not have all the records matched.

If I do join on any normal column/value then join works fine but when I tried to join on column having hash value then I have issue.

Please any suggest what could be the issue?

Thanks.
Rohit
priyadarshikunal
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Post by priyadarshikunal »

If the checksum value is different then it seems that the values are different or the data type is not identical or any padding is present while calculating the checksum. Also before join, you need to make sure that hash column has same metadata to get correct joins.

Since you are not getting the correct result while running in sequential mode, I think the issue is while calculating the check sum.
Priyadarshi Kunal

Genius may have its limitations, but stupidity is not thus handicapped. :wink:
rohit_mca2003
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Joined: Wed Oct 08, 2008 9:19 am

Post by rohit_mca2003 »

Hi,

I checked the checksum values and it is same what ever is in target. Also if DataStage generates different checksum for same value then it should not be used.

Thanks.
Rohit
priyadarshikunal
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Joined: Thu Mar 01, 2007 5:44 am
Location: Troy, MI

Post by priyadarshikunal »

It does not generate different checksum for the same value if the data type is identical as well including unicode.
Priyadarshi Kunal

Genius may have its limitations, but stupidity is not thus handicapped. :wink:
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