Names Matter

This is one of my favorite quotes: There are only two hard things in Computer Science: cache invalidation and naming things. — Phil Karlton IT is my daily live. And this quote is so true. Lately I’ve been thinking much more than usual about naming, and that names really matter. This led […]

Bitemp Remodeler v0.1.0 Released

I’ve been working on a flexible table API generator for Oracle Databases since several months. A TAPI generator doesn’t sound like a real innovation. But this one contains some features you probably have not seen before in TAPI generator and hopefully will like it as much as I do. In this post I will not […]

Multi-temporal Features in Oracle 12c

Oracle 12c has a feature called Temporal Validity. With Temporal Validity you can add one or more valid time dimensions to a table using existing columns, or using columns automatically created by the database. This means that Oracle offers combined with Flashback Data Archive native bi-temporal and even multi-temporal historization features. This […]

Joining Temporal Intervals Part 2

The solution I’ve provided in Joining Temporal Intervals produces wrong results if one or more temporal tables have gaps in their history or if disconnected intervals have the same content. In this post I’ll address both problems. Test Data The example queries are based on the same model as described in Joining Temporal […]

Merging Temporal Intervals with Gaps

In Joining Temporal Intervals I explained how to join multiple temporal tables. The provided solution merges also temporal intervals but – as pointed out in that post – may produce wrong results if the underlying driving table is not gaplessly historized. In this post I’ll explain how to merge temporal intervals with various […]

Joining Temporal Intervals

From time to time a customer asks me how to join multiple tables with temporal intervals (e.g. defined by two columns such as valid_from and valid_to per row). The solution is quite simple if you may limit your query to a certain point in time like now, yesterday or similar. Such a […]