SQL Server 2008 R2存储过程很慢

Question

我加入3个不同的表以实现自动完成功能，并且必须快速。建议必须回复良好且及时。我需要通过LIKE运算符来查看3个不同的字段以获得答案。见下面的细节。

DECLARE @Space AS CHAR(1) = ' '; 

SELECT TOP (@QuantityToReturn) * 
FROM 
    (SELECT 
      C.CMPID, C.CMPNAME, C.CMPTHEIRCODE, AD.ADTOWN 
     FROM COMPANY C 
     JOIN [dbo].[COMPADDRESS] CA ON CA.CMPID = C.CMPID 
     JOIN [dbo].[ADDRESS] ad ON AD.ADID = CA.ADID 
     JOIN [dbo].SUPPLIER SUP ON C.CMPID = SUP.CMPID 
     WHERE 
      (C.CMPID = @LoggedInUserId 
      OR @LoggedInUserId = dbo.fnIsAParentCompanyOf(@LoggedInUserId, C.CMPID) 
      OR @LoggedInUserId = 12345) 

     UNION 

     SELECT 
      C.CMPID, C.CMPNAME, C.CMP_THEIRCODE, AD.ADTOWN 
     FROM COMPANY C 
     JOIN [dbo].[COMPADDRESS] CA ON ca.CMPID = C.CMPID 
     JOIN [dbo].[ADDRESS] AD ON AD.ADID = CA.ADID 
     JOIN [dbo].CUSTOMER CUS ON C.CMPID = CUS.CMPID AND CUS.CUSTISTHIS = 1 
     WHERE 
      (C.CMPID = @LoggedInUserId 
      OR @LoggedInUserId = dbo.fnIsAParentCompanyOf(@LoggedInUserId, C.CMPID) 
      OR @LoggedInUserId = 12345) 
    ) AS Results 
     WHERE 
      (CMPNAME + @Space + ADTOWN + @Space + CMPTHEIRCODE) LIKE '%' + @Query + '%' 

上面的代码是缓慢（〜9sec）

• 如果我使用：WHERE CMPNAME LIKE '%' + @Query + '%' =快;
• 如果我使用：WHERE ADTOWN LIKE '%' + @Query + '%' = quick;
• 如果我使用：WHERE CMPTHEIRCODE LIKE '%' + @Query + '%' = quick;

只是当我连接它们变慢时？

Answer 1

我会尝试是这样的：

WHERE 
    LEN(@Query) <> LEN(REPLACE(@Query, CMPNAME, '')) 

    AND (LEN(@Query) <> LEN(REPLACE(@Query, ADTOWN, '')) 
     AND CHARINDEX(CMPNAME, @Query) = (CHARINDEX(ADTOWN, @Query) - 1 - LEN(CMPNAME)) 
     ) -- making sure that the value of ADTOWN comes after CMPNAME 

    AND (LEN(@Query) <> LEN(REPLACE(@Query, CMPTHEIRCODE, '')) 
     AND CHARINDEX(ADTOWN, @Query) = (CHARINDEX(CMPTHEIRCODE, @Query) - 1 - LEN(ADTOWN)) 
     ) -- making sure that the value of CMPTHEIRCODE comes after ADTOWN 

我试图重新实现你的3个条件的逻辑上，你有索引的列上的参数运行，而不是。我的假设是，在这种情况下，索引将被使用。

PS：当发现/减少charindex的结果时，需要进行小的调整migth，以防我在计算中犯了一些错误，但希望你明白了。 - SQLFiddle to validate that the CHARINDEX() comparisons are correct。

另外，我建议/尝试查询的顶部做一些修改，以便在年底你的脚本应该是这样的：

DECLARE @Space AS CHAR(1) = ' '; 

SELECT TOP (@QuantityToReturn) * 
FROM (
    SELECT C.CMPID 
     ,C.CMPNAME 
     ,C.CMPTHEIRCODE 
     ,AD.ADTOWN 
    FROM COMPANY C 
    INNER JOIN [dbo].[COMPADDRESS] CA 
     ON CA.CMPID = C.CMPID 
    INNER JOIN [dbo].[ADDRESS] ad 
     ON AD.ADID = CA.ADID 
    WHERE (
      C.CMPID = @LoggedInUserId 
      OR @LoggedInUserId = dbo.fnIsAParentCompanyOf(@LoggedInUserId, C.CMPID) 
      OR @LoggedInUserId = 12345 
      ) 
     AND EXISTS (
      SELECT 1 
      FROM [dbo].SUPPLIER SUP 
      WHERE C.CMPID = SUP.CMPID 
      ) 

    UNION 

    SELECT C.CMPID 
     ,C.CMPNAME 
     ,C.CMP_THEIRCODE 
     ,AD.ADTOWN 
    FROM COMPANY C 
    INNER JOIN [dbo].[COMPADDRESS] CA 
     ON ca.CMPID = C.CMPID 
    INNER JOIN [dbo].[ADDRESS] AD 
     ON AD.ADID = CA.ADID 
    WHERE (
      C.CMPID = @LoggedInUserId 
      OR @LoggedInUserId = dbo.fnIsAParentCompanyOf(@LoggedInUserId, C.CMPID) 
      OR @LoggedInUserId = 12345 
      ) 
     AND EXISTS (
      SELECT 1 
      FROM [dbo].CUSTOMER CUS 
      WHERE C.CMPID = CUS.CMPID 
       AND CUS.CUSTISTHIS = 1 
      ) 
    ) AS Results 
WHERE LEN(@Query) <> LEN(REPLACE(@Query, CMPNAME, '')) 
    AND (
     LEN(@Query) <> LEN(REPLACE(@Query, ADTOWN, '')) 
     AND CHARINDEX(CMPNAME, @Query) = (CHARINDEX(ADTOWN, @Query) - 1 - LEN(CMPNAME)) 
     ) -- making sure that the value of ADTOWN comes after CMPNAME 
    AND (
     LEN(@Query) <> LEN(REPLACE(@Query, CMPTHEIRCODE, '')) 
     AND CHARINDEX(ADTOWN, @Query) = (CHARINDEX(CMPTHEIRCODE, @Query) - 1 - LEN(ADTOWN)) 
     ) -- making sure that the value of CMPTHEIRCODE comes after ADTOWN 

希望它能帮助。