查询总共要查询的数据量

    CREATE TABLE #tablespaceinfo  
        (  
          nameinfo VARCHAR(50) ,  
          rowsinfo BIGINT ,  
          reserved VARCHAR(20) ,  
          datainfo VARCHAR(20) ,  
          index_size VARCHAR(20) ,  
          unused VARCHAR(20)  
        )    
       
    DECLARE @tablename VARCHAR(255);    
       
    DECLARE Info_cursor CURSOR 
    FOR 
        SELECT  ‘[‘ + [name] + ‘]‘ 
        FROM    sys.tables  
        WHERE   type = ‘U‘;    
       
    OPEN Info_cursor    
    FETCH NEXT FROM Info_cursor INTO @tablename    
       
    WHILE @@FETCH_STATUS = 0  
        BEGIN   
            INSERT  INTO #tablespaceinfo  
                    EXEC sp_spaceused @tablename    
            FETCH NEXT FROM Info_cursor    
        INTO @tablename    
        END   
       
    CLOSE Info_cursor    
    DEALLOCATE Info_cursor    
       
    --创建临时表  
    CREATE TABLE [#tmptb]  
        (  
          TableName VARCHAR(50) ,  
          DataInfo BIGINT ,  
          RowsInfo BIGINT ,  
          Spaceperrow  AS ( CASE RowsInfo  
                             WHEN 0 THEN 0  
                             ELSE CAST(DataInfo AS decimal(18,2))/CAST(RowsInfo AS decimal(18,2))  
                           END ) PERSISTED  
        )  
     
    --插入数据到临时表  
    INSERT  INTO [#tmptb]  
            ( [TableName] ,  
              [DataInfo] ,  
              [RowsInfo]  
            )  
            SELECT  [nameinfo] ,  
                    CAST(REPLACE([datainfo], ‘KB‘, ‘‘) AS BIGINT) AS ‘datainfo‘ ,  
                    [rowsinfo]  
            FROM    #tablespaceinfo  
            ORDER BY CAST(REPLACE(reserved, ‘KB‘, ‘‘) AS INT) DESC    
     
     
    --汇总记录  
    SELECT  [tbspinfo].* ,  
            [tmptb].[Spaceperrow] AS ‘每行记录大概占用空间（KB）‘ 
    FROM    [#tablespaceinfo] AS tbspinfo ,  
            [#tmptb] AS tmptb  
    WHERE   [tbspinfo].[nameinfo] = [tmptb].[TableName]  
    ORDER BY CAST(REPLACE([tbspinfo].[reserved], ‘KB‘, ‘‘) AS INT) DESC    
     
    DROP TABLE [#tablespaceinfo]  
    DROP TABLE [#tmptb]