Housekeeping: Added If a table with a SK has a NK does it violate 3NF? to LINKS page.
1. Quote of the Week
One other intriguing benefit of NoSQL that I started to unwitting benefit from recently is the ability to push data scheme concerns entirely to the application layer. In this scenario, the applications use a NoSQL database predominantly as a storage service, lightly structured by a few indexed key fields. The object structured data document within the payload becomes transparent to the database. The applications then assume the role of enforcing and understanding the data scheme.
This approach allows the application architect to encode the data structures and meaning directly in the code that creates and consumes the data. So data structure changes required for functional updates can be implemented, tested, and deployed in the application code base with no updates to the database layer at all. (Of course, a conversion of existing NoSQL data documents may be required in situations.)
In this NoSQL approach, the removed translation of object data scheme to a relational structure and, and then back to an object structure again is a very welcome relief as well. --use-the-index-luke.com
We've been there, done that.
In Coming Full Circle: Why SQL now powers the NoSQL Craze Ryan Betts, CTO at VoltDB, argues that NoSQL products should adopt SQL for queries. I don't know about you, but to me it looks like a contradiction. Let me make it clear that my intention here is neither to defend SQL, nor to criticize it--I sure have done enough of that during the years--but rather strictly debunk the notion that its use with NoSQL systems is a good idea.
Housekeeping: Added
to LINKS page.
RAQUEL
to SOFTWARE section on Home page.
1. Quote of the Week
After attending NoSQL conference I am really hoping that companies think through this 'big data' implementation! No one there was interested in Data model ... and said so ... forget the data model ... even 'standards' were looked at 'its 'too early' for this new technology ... and no one could tell us anything about 'meta-data'...!!!!! --LinkedIn.com
1. Quote of the Week
The ER notation consists a set of constructs, such as, a rectangle to represent an entity types, an ellipse to represent an attribute a diamond to represent a relationship type, and so on. The RDS is a set of linear relation schemas. A relation schema has a name and is a sequence of attributes of text separated by comas and arranged horizontal. I have also developed an ER-to relational transformation algorithm to transform an ER schema to its corresponding RDS. I wish to implement this project as a CASE tool. --LinkedIn.com
The problem is not the student, but the quality of education he gets at his university.
My October column @AllAnalytics.
We have seen that the usefulness of the relational data model (RDM) is
in its dual theoretical foundation -- first order predicate logic (FOPL)
and set theory -- the mathematics guarantees provable logical
correctness of query results regardless what meaning is assigned to the
database R-tables. But a logically correct result is not necessarily a meaningful
result. As a reader commented "If a is Salary and b is Start date, the
[Cartesian] product a*b still doesn't have a sensible meaning." It is
critical for the analyst to understand the distinction.
Read it all. (Please comment there, not here)
