任何有关优化以下查询的建议，这些查询包括普通和所有邻居？

该表由call_party和called_party列组成，记录描述两个用户之间的连接，其中一个扮演主叫方角色，另一个扮演主叫方角色。任何有关优化以下查询的建议，这些查询包括普通和所有邻居？

相同的两个用户可以有两个连接 - 在这种情况下，当方向改变时，角色主叫/被叫方被切换。

在原始表（monthly_connections）中，我添加了common_neighbors和total_neighbors的附加列，其中存储了常见邻居和总邻居的数量。为了澄清，术语共同和total_neighbors添加以下图像：

alt text

在这种情况下所观察到的连接有主叫的2个共同邻居和被叫方6个总邻居。

为了得到这两个值我写了下面的存储过程：

CREATE PROCEDURE [dbo].[spCountNeighbors] 

AS 

Declare 
@CallingParty varchar(50), 
@CalledParty varchar(50), 
@RecordsUpdated int 

SET @CallingParty ='a' 
SET @RecordsUpdated = 0 
PRINT GETDATE() 
WHILE @CallingParty IS NOT NULL BEGIN 
    SET @CallingParty = NULL 
    SELECT TOP 1 @CallingParty = calling_party, @CalledParty = called_party FROM monthly_connections WHERE common_neighbors IS NULL 
    --PRINT @CallingParty 
    IF @CallingParty IS NOT NULL BEGIN 
    WITH callingPartyNeighbors AS 
    (
     SELECT called_party as neighbor FROM monthly_connections WHERE calling_party = @CallingParty 
     UNION 
     SELECT calling_party as neighbor FROM monthly_connections WHERE called_party = @CallingParty 
    ), 
    calledPartyNeighbors AS 
    (
     SELECT calling_party as neighbor FROM monthly_connections WHERE called_party = @CalledParty 
     UNION 
     SELECT called_party as neighbor FROM monthly_connections WHERE calling_party = @CalledParty 
    ) 

     UPDATE mc SET common_neighbors = (SELECT COUNT (*) FROM 
     (
     SELECT neighbor FROM callingPartyNeighbors 
     INTERSECT 
     SELECT neighbor FROM calledPartyNeighbors 
     ) 
     t1 
     ), 
     total_neighbors = (SELECT COUNT (*) FROM 
     (
     SELECT neighbor FROM callingPartyNeighbors 
     UNION 
     SELECT neighbor FROM calledPartyNeighbors 
     ) 
     t2 
     ) 
     FROM monthly_connections mc WHERE (mc.calling_party = @CallingParty AND mc.called_party = @CalledParty) OR (mc.called_party = @CallingParty AND mc.calling_party = @CalledParty); 
     SET @RecordsUpdated = @RecordsUpdated + @@ROWCOUNT 
     PRINT @RecordsUpdated 
    END 
END 
PRINT @RecordsUpdated

的程序上面应该去通过连接其中包含的每一行23M的连接和更新值common_neighbors和total_neighbors表。然而，问题在于程序太慢 - 更新1000条记录需要212秒。

为了加快执行时间，我真的很感谢你们中的任何人提出了上述过程的任何修正。

谢谢！

来源

2010-11-22 Niko Gamulin

以下脚本会为您的存储过程生成与common_neighbors相同的输出。不过，尽管如此，我感觉它并不完全（但）是你需要的，但是你可能会为它提出一些新的想法。

DECLARE @monthly_connections TABLE (
    calling_party VARCHAR(50) 
    , called_party VARCHAR(50) 
    , common_neighbors INTEGER 
    , total_neighbors INTEGER) 

INSERT INTO @monthly_connections 
      SELECT '1', '3', NULL, NULL 
UNION ALL SELECT '2', '4', NULL, NULL 
UNION ALL SELECT '3', '2', NULL, NULL 
UNION ALL SELECT '3', '4', NULL, NULL 
UNION ALL SELECT '3', '6', NULL, NULL 
UNION ALL SELECT '3', '7', NULL, NULL 
UNION ALL SELECT '4', '5', NULL, NULL 
UNION ALL SELECT '8', '4', NULL, NULL 

;WITH q AS (
    SELECT calling_party, called_party 
    FROM @monthly_connections mc1 
    UNION ALL 
    SELECT called_party, calling_party 
    FROM @monthly_connections mc1 
) 
UPDATE @monthly_connections 
SET  common_neighbors = common_neighbors.cnt 
FROM @monthly_connections mc 
     INNER JOIN (
      SELECT q1.calling_party, q1.called_party, cnt = COUNT(*) 
      FROM q q1 
        INNER JOIN q q2 ON q2.calling_party = q1.called_party       
        INNER JOIN q q3 ON q3.calling_party = q2.called_party 
            AND q3.called_party = q1.calling_party 
      GROUP BY 
        q1.calling_party, q1.called_party 
     ) common_neighbors ON common_neighbors.calling_party = mc.calling_party 
           AND common_neighbors.called_party = mc.called_party 


SELECT * 
FROM @monthly_connections

来源

2010-11-22 10:53:59

在你的程序中，你正在做很多的子查询，我想这是你的性能损失的主要来源。难道你不能只用一个大连接替换多个查询，然后过滤它吗？喜欢的东西

SELECT T.calling_party, T.called_party, A.called_party, B.called_party 
from table T 
join table as A 
on T.calling_party = A.calling_party 
join table as B 
on T.calling_party = B.calling_party 
where A.called_party = B.called_party --to get the commong neighbour

你可能会需要另一个加盟的called_party得到完整的名单，但我认为这可能比通过23M记录迭代，并呼吁所有的人都多次查询速度更快。

来源

2010-11-22 09:49:46

任何有关优化以下查询的建议，这些查询包括普通和所有邻居？

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