Re-Keying Surrogate Key For Dimension & Fact Tables. Need, Impact and Fix

Re-Keying Surrogate Key For Dimension & Fact Tables. Need, Impact and Fix

A surrogate key is an artificial key that is used as a substitute for a natural key. Every surrogate key points to a dimension record, which represent the state of the dimension record at a point in time. We join between dimension tables and fact tables using surrogate keys to get the factual information at a point in time. In this article lets see the need of surrogate key re-keying, the impact of re-keying and possible fix.

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Initial History Building Algorithm for Slowly Changing Dimensions

Initial History Building Algorithm for Slowly Changing Dimensions

Building initial history for a Data Warehouse is a complex and time consuming task. It involve taking into account of all the date intervals from different source tables during which the source system’s representation of data in any of the tables feeding into the Dimension Tables. So we can imagine the history building complexity and the need of a reusable algorithm.

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