Each table in SQL Server database has an owner. It could either be default owner (dbo) or actual user. A table created by a member of the sysadmin fixed server role will get dbo as owner.
If you don't specify an owner (mydb..mytable), SQL Server will first look for a table that belongs to the currently logged user. If such table doesn't exists, than dbo is used as an owner. Specifying dbo may speed up querie because it eliminates one extra object lookup.

>I have seen this "dbo" notation before but it has usually caused me grief. There doesn't seem to be much in the thelp about it. What is it exactly?
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