Execute the following Microsoft SQL Server T-SQL scripts in SSMS Query Editor to list all database sizes in megabytes.

USE AdventureWorks2008;

GO

-- Using undocumented system procedure

EXEC sp_MSforeachdb

  @command1 = "select '?', 0.0078125 * sum(size) from ?..sysfiles"

GO

-- T-SQL find total size of all databases

SELECT STR(CONVERT(NUMERIC(18),SUM(size)) * 0.0078125,10,2) + ' MB'

FROM master.dbo.sysaltfiles

GO

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Capturing SQL Server 2005 database file size information