Databases Reference
In-Depth Information
apply to fact tables the same way they apply to dimension
tables. We are developing a methodology for supporting
both versioning, and the as-was vs. as-is distinction, in
both fact and dimension tables.
Going Forward
We thank our readers who have stuck with us through an
extended discussion of some very complex ideas. For those
who would like to learn more about bi-temporal data, and about
Asserted Versioning, we recommend that you visit our website,
AssertedVersioning.com, and our webpage at Elsevier.com.
At our website, we have also created a small sample database
of asserted version tables. Registered users can write both main-
tenance transactions and queries against that database. Because
these tables contain data from all nine temporal categories, we
recommend that interested readers first print out the contents
of these tables before querying them. It is by comparing the full
contents of those tables to query result sets that the work of each
query can best be understood, and the semantic richness of the
contents of Asserted Versioning databases best be appreciated.
Glossary References
Glossary entries whose definitions form strong inter-
dependencies are grouped together in the following list. The
same glossary entries may be grouped together in different ways
at the end of different chapters, each grouping reflecting the
semantic perspective of each chapter. There will usually be sev-
eral other, and often many other, glossary entries that are not
included in the list, and we recommend that the Glossary be
consulted whenever an unfamiliar term is encountered.
ad hoc query
production query
Allen relationships
time period
as-is query
as-was query
asserted version table
assertion
assertion time
