To know the Sql Server database size, following stored procedure can be executed.
-- This will give you the complete database size including log file
-- This will give you the number of rows in the table and space used for this table
exec sp_spaceused "MyTable"
Here "reserved" column gives you the complete size of this table.
You can also see the actual size of the database file and log file separately by executing following command.
select * from sysfiles