Spaced Used by a table in a specific database.

Shows you how to get the SQL Server database table size
EXEC SP_SPACEUSED 'TABLE NAME'

Shows you how to get the size of a database
EXEC SP_SPACEUSED

Shows you how to get the all tables size from database
EXEC sp_MSforeachtable @command1="EXEC sp_spaceused '?'"

–--create temp table to store the result
CREATE TABLE #temptable
  (
     tablename    VARCHAR(100),
     numberofrows VARCHAR(100),
     reservedsize VARCHAR(50),
     datasize     VARCHAR(50),
     indexsize    VARCHAR(50),
     unusedsize   VARCHAR(50)
  )

---Inserting into temp table
INSERT INTO #temptable
            (tablename,
             numberofrows,
             reservedsize,
             datasize,
             indexsize,
             unusedsize)

EXEC sp_MSforeachtable @command1="EXEC sp_spaceused '?'"

SELECT *
FROM   #temptable
---drop the temporary table
DROP TABLE #temptable