Tsql for database , size , free space or used space in database

Question

hi,
 i want to know how to find out database size

Answer 1

use master
declare @PageSize varchar(10)
select @PageSize=v.low/1024.0
from master..spt_values v
where v.number=1 and v.type='E'
select name as DatabaseName, convert(float,null) as Size
into #tem
From sysdatabases where dbid>4
declare @SQL varchar (8000)
set @SQL=''
while exists (select * from #tem where size is null)
begin
select @SQL='update #tem set size=(select round(sum(size)*'+@PageSize+'/1024,0) From '+quotename(databasename)+'.dbo.sysfiles) where databasename='''+databasename+''''
from #tem
where size is null
exec (@SQL)
end
select * from #tem order by DatabaseName
drop table #tem
The first select statement is to get how many kilobytes a data page has. SQL Server allocates disk space in the unit of data page. Currently each SQL server data page contains 8k bytes. The number of data pages allocated to each database file is recorded
in the sysfiles system table. With this information on hand the script creates a temporary table #tem and update the temporary table with size information which is gathered by querying the sysfiles table.
thx benedikt