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Informatica - What is the difference between cached and uncached look ups?




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asked marvit September 20, 2014 07:58 AM  

What is the difference between cached and uncached look ups?


           

1 Answers



 
answered By vishnoiprem   0  
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 rowsGo for UnCache lookup if Lookup table size> Mapping rows
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.
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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