146.逐级汇总-案例

刺骨的言语ヽ痛彻心扉 2024-02-19 19:10 42阅读 0赞

#### 1.用户自定义函数 ####

CREATE TABLE tb(ID int PRIMARY KEY,PID int,Num int)
    INSERT tb SELECT 1,NULL,100
    UNION ALL SELECT 2,1   ,200
    UNION ALL SELECT 3,2   ,300
    UNION ALL SELECT 4,3   ,400
    UNION ALL SELECT 5,1   ,500
    UNION ALL SELECT 6,NULL,600
    UNION ALL SELECT 7,NULL,700
    UNION ALL SELECT 8,7   ,800
    UNION ALL SELECT 9,7   ,900
    GO
    
    --得到每个节点的编码累计
    CREATE FUNCTION f_id()
    RETURNS @t TABLE(ID int,Level int,SID varchar(8000))
    AS
    BEGIN
    	DECLARE @Level int
    	SET @Level=1
    	INSERT @t SELECT ID,@Level,','+CAST(ID as varchar)+','
    	FROM tb
    	WHERE PID IS NULL
    	WHILE @@ROWCOUNT>0
    	BEGIN
    		SET @Level=@Level+1
    		INSERT @t SELECT a.ID,@Level,b.SID+CAST(a.ID as varchar)+','
    		FROM tb a,@t b
    		WHERE a.PID=b.ID
    			AND b.Level=@Level-1
    	END
    	RETURN
    END
    GO
    
    --调用函数实现实现累计
    SELECT a.ID,a.PID,a.Num,SUM_Num=SUM(b.Num)
    FROM tb a,f_id() a1,
    	tb b,f_id() b1
    WHERE a.ID=a1.ID
    	AND b.ID=b1.ID
    	AND b1.SID LIKE a1.SID+'%'
    GROUP BY a.ID,a.PID,a.Num
    /*--结果
    ID          PID         Num         SUM_Num 
    ---------------- ------------------ ------------------- -------------------- 
    1           NULL       100         1500
    2           1           200         900
    3           2           300         700
    4           3           400         400
    5           1           500         500
    6           NULL       600         600
    7           NULL       700         2400
    8           7           800         800
    9           7           900         900
    --*/

#### 2.循环组件累计法 ####

CREATE TABLE tb(ID int PRIMARY KEY,PID int,Num int)
    INSERT tb SELECT 1,NULL,100
    UNION ALL SELECT 2,1   ,200
    UNION ALL SELECT 3,2   ,300
    UNION ALL SELECT 4,3   ,400
    UNION ALL SELECT 5,1   ,500
    UNION ALL SELECT 6,NULL,600
    UNION ALL SELECT 7,NULL,700
    UNION ALL SELECT 8,7   ,800
    UNION ALL SELECT 9,7   ,900
    GO
    
    --计算的存储过程
    CREATE PROC p_Calc
    AS
    SET NOCOUNT ON
    DECLARE @Level int
    SET @Level=1
    
    SELECT ID,PID,SUM_Num=Num,
    	Level=CASE 
    		WHEN EXISTS(SELECT * FROM tb WHERE PID=a.ID)
    		THEN 0 ELSE 1 END
    INTO # FROM tb a
    
    WHILE @@ROWCOUNT>0
    BEGIN
    	SET @Level=@Level+1
    	UPDATE a SET 
    		Level=@Level,
    		SUM_Num=ISNULL(a.SUM_Num,0)+ISNULL(b.SUM_Num,0)
    	FROM # a,(
    		SELECT aa.PID,SUM_Num=SUM(aa.SUM_Num)
    		FROM # aa,(SELECT DISTINCT PID FROM # WHERE Level=@Level-1)bb
    		WHERE aa.PID=bb.PID
    			AND NOT EXISTS(
    				SELECT * FROM # WHERE PID=aa.PID AND Level=0)
    		GROUP BY aa.PID
    	)b WHERE a.ID=b.PID
    END
    SELECT a.*,b.SUM_Num
    FROM tb a,# b
    WHERE a.ID=b.ID
    GO
    
    --调用存储过程进行计算
    EXEC p_Calc
    /*--结果
    ID          PID         Num         SUM_Num 
    ---------------- ------------------ ------------------- -------------------- 
    1           NULL       100         1500
    2           1           200         900
    3           2           300         700
    4           3           400         400
    5           1           500         500
    6           NULL       600         600
    7           NULL       700         2400
    8           7           800         800
    9           7           900         900
    --*/