SQL Server and tables? Invalid object

Firstly I'm a complete newbie when it comes to SQL Server. I have five SQL Server databases, in all of them except one I can easily do say...

SELECT TOP 10 * FROM dt_Organizers

However one of the new databases require me to do this:

SELECT TOP 10 开发者_JS百科* FROM dbuser.dt_Organizers

Note that all the tables in all databases have "dbuser" "dbamy" "dbyon" "dbmio" "dbcana" prefixes respectively, this never caused a problem before. Now if I use the query without doing dbuser.dt_Organizers it brings up:

Warning: mssql_query()

[function.mssql-query]: message:

Invalid object name 'dt_Organizers'.

I think you should have a look at

• Understanding the Difference between Owners and Schemas in SQL Server
• SQL SERVER – Importance of Database Schemas in SQL Server