difference b/w Oracle stage & Flat file Stages

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sudheepkv
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difference b/w Oracle stage & Flat file Stages

Post by sudheepkv »

Hi,

1 What is the difference between an oracle stage lookup and Flat file stage lookup in a parrel job?Plz explain

2 What is the advatage of using lookup file set as a lookup
sudhi
kumar_s
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Post by kumar_s »

Hi,

1.Oracle stage is used because the source(lookup file set) is in RDBMS format. If the same is aviable in Flat file, then it becomes the lookup set.
Performance wise, flat file might be in the later part, since it works in sequenctial partion.

2.Lookup file set need to be prepared prior to the use. It sort and hash the data internally based on the key on which it suppose to lookup on. Hence it works faster when loaded into lookup memory.

-Kumar
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