Informatica - Cached Lookup and an Uncached Lookup

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Cached Lookup and an Uncached Lookup

What is the difference between using a cached lookup and an uncached lookup?

Total Answers and Comments: 3

Last Update: January 08, 2009 Asked by: rajneeshpandey83

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Submitted by: ggazulas

For a cached lookup the entire rows (lookup table) will be put in the buffer, and compare these rows with the incomming rows.

where as uncached lookup, for every input row the lookup will query the lookup table and get the rows.

Above answer was rated as good by the following members:
avneeshrathor

May 07, 2008 23:59:57

vivek1708

Member Since: May 2008 Contribution: 18

RE: Cached Lookup and an Uncached Lookup

while using a cache lookup a pre-fetch is performed on the lookup table before the mapping is executed.

Uncached lookup is like any normal look up.

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May 27, 2008 09:40:20

ggazulas

Member Since: May 2008 Contribution: 6

RE: Cached Lookup and an Uncached Lookup

For a cached lookup the entire rows (lookup table) will be put in the buffer and compare these rows with the incomming rows.

where as uncached lookup for every input row the lookup will query the lookup table and get the rows.

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Overall Rating: +1

January 08, 2009 02:12:07

gaurav2485

Member Since: January 2009 Contribution: 12

RE: Cached Lookup and an Uncached Lookup

In Cache Lookup a cache will be created of that Lookup table and IS query once for mapping rows for Uncache lookup No cache will be build and IS query for each Mapping rows.
So for performance Go for Cache lookup if Lookup table size< Mapping rows
Go for UnCache lookup if Lookup table size> Mapping rows

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