One of the big plusses for nosql DBMS is that they can cluster more easily. Supposedly with NoSQL you can create hundreds of cheap machines that store different pieces of data and query it all at ...
I have this relation: R = ABCDE F: AB->DE, AC->B, DE->C, AE->C, C->AB. Is AC->B a partial dependency in F? I'm guessing it is, because C->AB can be decomposed to C->A C->B ...
Background Most modern databases have XML functions that can be used to extract data in an XML format. I want to avoid the task of manually calling XML functions to extract the data. This problem ...
The ANSI SQL standard defines (chapter 6.5, set function specification) the following behaviour for aggregate functions on empty result sets: COUNT(...) = 0 AVG(...) = NULL MIN(...) = NULL MAX(...) = ...
I have a problem with second normal form (2NF) and I have been unable to solve it by using Google. It is making me crazy because I am a teacher and I don't want to teach wrong stuff to my students. ...
In my Database Design course we are learning both Relational Algebra and Relational Calculus. I can see where Relational Algebra could be useful since it is closely tied to SQL. Our professor said ...
I am looking for advice on the best relational modeling approach to store surveys, questions, and responses. I am looking for which of the two approaches below looks best, or an alternative approach ...