Hi,
am new to datastage, what is the meaning of indexing in datastage, how to index keys in join or lookup or in datastage
Thanks in advance
indexing
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Since DataStage does not store data, it does not have or need indexes of any kind*. Therefore the term "indexing" is meaningless in the context of ETL.
However, certain database stages do include the ability to specify how to handle indexes when loading data into the tables, for example to drop and subsequently re-build the indexes. But I don't feel that that fits into the context of your question.
When's the interview?
* Actually, there is one case; the LUT_CreateOp operator, which loads a reference data set into memory and builds a hash table to index those data "on the fly" or, if loading from a Lookup File Set, by reading the index from the Lookup File Set.
However, certain database stages do include the ability to specify how to handle indexes when loading data into the tables, for example to drop and subsequently re-build the indexes. But I don't feel that that fits into the context of your question.
When's the interview?
* Actually, there is one case; the LUT_CreateOp operator, which loads a reference data set into memory and builds a hash table to index those data "on the fly" or, if loading from a Lookup File Set, by reading the index from the Lookup File Set.
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Any contribution to this forum is my own opinion and does not necessarily reflect any position that IBM may hold.