The power of Cross (Cartesian) Joins

This is a very good example of where the Cartesian (Cross) Join may be very helpful. Though proper understanding and enough experimentation should be done to try it out.
Jeff @ SQLTeam.com

It explains an example where a Join may be required to return some value ['0'] in this case when there are no matching records found. for e.g. return 0 for sales of all combination of products and stores which dont have a value i.e. null.


SELECT S.Store, P.Product, ISNULL(C.TotalSales,0) as TotalSales
FROM Stores S
CROSS JOIN Products P
LEFT OUTER JOIN
(SELECT Store, Product, SUM(Sales) as TotalSales
FROM Sales
GROUP BY Store, Product) C
ON
S.Store = C.Store AND
P.Product = C.Product

Also Refer:
Join Clause in SQl

The Golden Rule of Data Manipulation

This is a very good post about data design.
SQLTeam Golden Rule Of Data manipulation

It is suggested that Concatenating is easier than parsing scripts. Thus wherever possible one must segregate the data. e.g Full name phone numbers etc.