In some dimension, we may find that we don't have any dimension attributes but only its business key. Transaction Number is an example, other transaction header's attributes are logically organized in other dimensions. (e.g. Transaction date is organized to Date dimension) It doesn't make sense to create a tiny dimension with just the surrogate key and business key. So, we may consider to degenerate the dimension and store the business key (e.g. transaction number) in the fact table. Size and the content nature would be the way of our consideration (e.g. we degenerate the invoice number but not the invoice remarks). We call such a degenerated field in the fact table as the degenerated dimension.
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Extract: Performance Tips
Below listed some common performance tips for extract queries. Extract required columns only and specify in the query, avoid select * Extrac...
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Below listed some common performance tips for extract queries. Extract required columns only and specify in the query, avoid select * Extrac...
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The data warehouse / data mart are usually implemented in RDBMS. RDBMS provides lots of features to manage data which are useful for both op...
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In traditional data modeling, we usually add "created date", "last modified date", "created by" and "last...
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