Sparse Lookup

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vamsi.4a6
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Sparse Lookup

Post by vamsi.4a6 »

I read Sparse lookup can be used only when the reference link is Database.Just want to know if it can be still used if ref link is sequential file?
dr.murthy
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Re: Sparse Lookup

Post by dr.murthy »

No, Sparse lookup supports for DB stages only
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jerome_rajan
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Post by jerome_rajan »

And only for DB2 and Oracle, I believe.
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vamsi.4a6
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Post by vamsi.4a6 »

Thanks for the input.Could you plese clarify below doubts?

1)I did not find any option in Lookup Stage to select the sparse Lookup property?Could you please help me where to select that property?

2)Why should not we use Sparse lookup for sequetail file stage?
dr.murthy
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Post by dr.murthy »

You cannot see this option in Lookup stage, when you use the DB stage as a reference you can see this option in DB stage properties tab.
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jerome_rajan
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Post by jerome_rajan »

Sparse Lookup is a concept that's based on moving the processing of a join(lookup) to a database. Essentially, DataStage will send your rows in the stream link one by one to the reference DB and the join will be performed in the DB. Since join is a relational concept and does not apply to non-structured data like flat files, you cannot use a non-DB stage
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