alter database using variables?

I am trying to alter large numbers of databases and I wanted to insert a variable into the alter database command. I keep getting errors.

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declare @dbname nvarchar(100)
set @dbname = 'TestDB'
alter database @dbname set offline with rollback immediate

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Server: Msg 170, Level 15, State 1, Line 3
Line 3: Incorrect syntax near '@dbname'.
Server: Msg 102, Level 15, State 1, Line 3
Incorrect syntax near 'immediate'.
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When I substitute the TestDB value for @dbname, it works fine. Any help is appreciated.

You would need to use dynamic SQL.

MeanOldDBA
derrickleggett@hotmail.com

When life gives you a lemon, fire the DBA.

Many thanks Madhivanan. Guess a good SQL scripting book may a better way to learn than books online...

Matt

how would you do this:
--declare variables for first database
DECLARE @db1 nvarchar(100)
DECLARE @db1_LOG nvarchar(100)
DECLARE @db1_dfile nvarchar(512) --destination of file location leave same if not moving
DECLARE @db1_lfile nvarchar(512) --destination of log location leave same if not moving

SET @db1 = 'testdb';
SET @db1_dfile = 'Crogram FilesMicrosoft SQL ServerMSSQL.2MSSQLDATA estdb.mdf';
SET @db1_lfile = 'Crogram FilesMicrosoft SQL ServerMSSQL.2MSSQLDATA estdb_log.ldf';

SET @db1_log = @db1+'_log';

--takes database offline and move files
EXEC('ALTER DATABASE '+@db1+' SET OFFLINE')

EXEC('ALTER DATABASE '+@db1+' MODIFY FILE (NAME = '+@db1+', FILENAME ='+@db1_dfile+')')
I can't get the Filename='@db1_dfile'+')' part to work because of the extra ' needed on either side of the file path. Is that possible? I wanted to build a script to easily move serveral databases

I will recommend the variable SQL, it will help you alot.To get much awarness just check w3schools.com.