Oracle Table Elimination

We have shown that table elimination is used in the Oracle query optimizer, at least since version 10gR2. It is also present in the Express Edition (XE). Both historized and non-historized attributes are eliminated from queries using the latest view, as shown in the proof of concept script found here.

In order to get table elimination to work in Oracle we had to rewrite the SQL-code for the latest view to suit PL/SQL. It should however be semantically equivalent to the Transact-SQL version used in SQL Server. Using AUTOTRACE to run some queries shows that the table elimination is in effect.

Toolkit available (now deprecated)

We have released a toolkit for automating the generation of tables and collapsing views. The toolkit contains an XML Schema specification for anchor models, together with an XML file of an example model, and an XSLT translating the XML into an SQL Server 2005 script. The script sets up all tables with indexes as well as the latest and point-in-time collapsing views. We will continue our work on this “tool” in order to simplify its use.

AnchorModeling Toolkit v0.3.4

Please note that this toolkit has been deprecated in favor of the online modeling tool.