Error of finding a database size using a SQL query in SQL Server 2008 on Windows 7 -

i use sql query find size of databases in sql server 2008 ms sql server management studio.

i run sql query:

 select       d.name,      round (sum(mf.size) * 8 / 1024, 0) size_mbs        sys.master_files mf  inner join       sys.databases d on d.database_id = mf.database_id        d.database_id > 4 -- skip system databases      , d.name = 'my_database'  -- after removing this, still cannot find 'my_database' in results.  group       d.name  order       d.name 

my_database has been set on server result show nothing , cannot find it!

any appreciated.

thanks !

check user running has permission see database. try logging sql management studio using credentials , connection string running query with.