The primary key of fact table can simply be all its dimension keys (including degenerated dimensions) which are all columns except measures. Sometimes, it doesn't necessary to be all dimension keys since there may be some redundant information in dimensions. We usually don't need to generate a surrogate key for the fact table but simply use the composite primary key from those dimension keys columns. This primary key is also aligned to the granularity of the fact table.
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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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