Decomposition of a relation into join of projections serves as motivation for database normalization theory. In relational lattice terms relation
x projected into sets of attributes (that is empty relations)
x = (x v s) ^ (x v t)
Lets investigate dual perspective and switch the roles of join and inner union:
x = (x ^ s) v (x ^ t)
Hi all, From long time, I am planning to start a blog section on PL/SQL programming tips. I have observed that as we grow more in technology, we skip some of the key features of language. When discovered later, the same tip appears to be an important bottleneck in programming.
As some of you may recall, we started a new qualification procedure for this playoff, in which a selected subset of the top-25 ranked players are asked to take three qualifier quizzes to verify their outstanding performance in the previous quarter.
For the Q1 2012 playoff, we asked six players to take the qualifier quizzes.
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He is included in a massive and quite beautiful book titled "Raw+Material=Art".
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Many players have had the pleasure of submitting a quiz and then seeing it played by hundreds of developers aroudn the world. If you have not yet done so, I encourage you to give it a try.
Other players review quizzes to help us make sure they are free of errors and as interesting as can be.
All of these people provide content that usually benefits from HTML tags, especially showing code in a fixed font format.
A player submitted this request yesterday:
I just wonder that are you planning to open forum in pl/sql challenge?
Because I really would like to discuss and talk about quizzes. I think
the only shortage in this site is forum. There should be a forum for
users in order to discuss and talk about quizzes. Please do something for
Thanks for your help."