SQL Join Venn Diagrams

There's a great article on coding horror showing the visual represenatation of SQL Joins using Venn Diagrams.

SOURCE:
http://www.codinghorror.com/blog/2007/10/a-visual-explanation-of-sql-joins.html

SQL SERVER – Fix : Error: 4064

SQL SERVER 2005 – Fix : Error: 4064 – Cannot open user default database. Login failed. Login failed for user.

CAUSE:
The default database for the user is not accessible, this stops the user from logging in.

SOLUTION:
- Login Prompt->Connection Properties Tab->Connect to database field
- Change the database name to master.
- Once logged in, update the user's default database:

ALTER LOGIN [user] WITH DEFAULT_DATABASE = master

Source:
http://blog.sqlauthority.com/2008/11/04/sql-server-fix-error-4064-cannot-open-user-default-database-login-failed-login-failed-for-user/