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This is a continuously updated collection of old articles, method overviews and techniques made available to the whoever
is interested. Some detailed whitepapers are also avaliable to customers and prospective customers. As most of this material
takes effort to transform it for publication in a medium such as this, we will periodically be putting more material on the
public domain. We are looking forward to comments, corrections or suggestions.
Aggregation Strategy
- Aggregation Strategy Overview: An overiew of topics addressed by our methodology for deploying an Aggregation Strategy for dimensional models. The overniew
is cross-linked to other documents that descript some of the concepts. We offer a comprehensive package of services to help
organizations get a quick start.
"The Relational Taboo" and Nested Sets
This was the name of my original article, published in the October/November 1992 issue of the Relational Journal,
that proposed a way to effectively make ancestor-descendent searches in hierarchies working around relational
database limitations, i.e. the lack of recursion capability. Since then variants on the technique appeared at
trade journals and books. An excellent explanation is included in the "SQL for Smarties" by J. Celco as
well as his more recent "Trees and Hierarchies in SQL fr Smarties". The technique has also been employeed in
commercial products, such as People Soft's suite and in home-grown database designs.
Here you will find the original article circa 1992, along with creative ideas I have deployed in various implementations
of the technique that has never - to my knowledge - been published before, such as a pure SQL query to generate
the L/R enumeration.
- The Relational Taboo: Original Recursive Hierarchies article published in the 1992 -October/November issue of Codd and Date's Relational Journal.
- SQL Enumeration Algorithm: Using third generation SQL enhancements, such as the recursive union, it is now possible to generate the L/R enumeration
without procedural constructs. Check it out...
The SQL Corner
- Contiguous Counts: SQL query to compute number of contiguous facts within groups by date or period. useful for computing contiguous weeks
of sales or consecutive weeks out-of-stock etc.
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