Tagged: DV2.0

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Data Engine Thinking – the book

Data Engine Thinking – the book by Roelant Vos and Dirk Lerner – provides a full and in-depth overview of everything you need to develop a data solution that can stand both the test of time and the real world.

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End dating, or not, in Data Vault

End dating Satellites in Data Vault has much more than meets the eye. This post lays out various options and consideration that may help decide whether to implement end-dating, or not.

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The Data Warehouse Time Machine: synchronising model and automation metadata versions

I’ve completed a fairly large body of work that I’ve been meaning to do for a long time: how to automatically version the Data Warehouse data model in sync with the version of the ETL automation metadata. Although versioning models and code is relevant (but rarely implemented) in the traditional ETL area, this requirement to becomes very real when moving to a virtualised Data Warehouse / integrated model approach (Data Vault 2.0 in my case)....

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NoETL – Data Vault Link Satellite tables (part 1)

The final of the series of planned posts (for now at least) about Data Warehouse Virtualisation is all about Link Satellites. As with some of the earlier posts there are various similarities to the earlier approaches – most notably the Satellite virtualisation and processing. Concepts such as zero records and ‘virtual’ or computed end-dating are all there again, as are the constructions of using subqueries to do attribute mapping and outer queries to calculate hash...

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NoETL – Data Vault Link tables

Virtualising Data Vault Link structures follows a similar process to that of the virtual Hubs, with some small additions such as the support for (optional) degenerate attributes. To make things a bit more interesting I created some metadata that requires different Business Key ‘types’ so this can be shown and tested in the virtualisation program. For the example in this post I created three Link definitions (the metadata), one of which (LNK_CUSTOMER_COSTING) has a three-way relationship with the following...

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Quick and easy referential integrity validation (for dynamic testing)

This post is in a way related to the recent post about generating some test data. In a similar way I was looking for ways to make life a bit easier when it comes to validating the outputs of Data Vault ETL processes. Some background is provided in an earlier post on the topic of Referential Integrity (RI) specifically in the context of Data Vault 2.0. In short, by adopting the hash key concepts it...

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NoETL – Data Vault Satellite tables

The recent presentations provides a push to wrap up the development and release of the Data Vault virtualisation initiative, so now everything is working properly the next few posts should be relatively quick to produce. First off is the Satellite processing, which supports the typical elements we have seen earlier: Regular, composite, concatenated business keys with hashing Zero record provision Reuse of the objects for ETL purposes if required As this is another process going...

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Zero / ghost records in Data Vault Satellites versus Point In Time (PIT) tables

As posted earlier recent evolution of the Data Vault 2.0 conventions aim to remove the creation of zero records (or ‘ghost records’) in Satellites. Zero records have the sole aim of making sure that every business key in a Satellite has a complete timeline (e.g. 1900-01-01 to 9999-12-31) so that records are always returned when you query the state of the world at any given date. For instance if a certain record is created in...