存儲過程提高性能

Question

我寫了一個與我的Visual Basic .NET代碼完全相同的存儲過程。現在我已經對它們進行了基準測試。使用while循環和for循環。但是，兩者都給我帶來了更糟糕的結果，即使用我的Visual Basic .NET代碼。有什麼辦法改善這種代碼的性能：

DECLARE @RelationCode nvarchar(50) 
DECLARE @CompanyName nvarchar(256) 
DECLARE @IncomingInvoice decimal(18, 2) 
DECLARE @OutgoingInvoice decimal(18, 2) 
DECLARE @Profit decimal(18, 2) 
DECLARE @RelationTable as TABLE (RELATIONCODE nvarchar(10), COMPANY nvarhar(120)) 

INSERT INTO @RelationTable (RELATIONCODE, COMPANY) SELECT [fms].[dbo].[Relation].[RELATIONCODE], [fms].[dbo].[Relation].[COMPANYNAME] FROM [fms].[dbo].[Relation] 

/* Result table */ 
DECLARE @RESULTTABLE TABLE (RelationCode nvarchar(50), Companyname nvarchar(256), IncomingInvoice nvarchar(50), OutgoingInvoice nvarchar(50), profit nvarchar(50)) 

WHILE EXISTS(SELECT * FROM @RelationTable) 
BEGIN 
SELECT TOP 1 @RelationCode = RELATIONCODE, @CompanyName = COMPANY FROM @RelationTable 

    SELECT fmsTotalAmountIncoming INTO TempIncomingAmounts FROM (
      SELECT SUM(CASE WHEN fms1.currency != 'EUR' 
       THEN fms1.amount * fms1.rate 
      ELSE ISNULL(fms1.amount, 0) END) fmsTotalAmountIncoming 
    FROM [fms].[dbo].[file] f 
     INNER JOIN [fms].[dbo].[incominginvoiceline] fms1 ON 
     fms1.filenumber = CONVERT(NVARCHAR, f.filenumber) 
    WHERE f.RELATIONCODE = @RelationCode 
    ) a 

    SELECT fmsTotalAmountOutgoing INTO TempOutgoingAmounts FROM (
      SELECT SUM(CASE WHEN fms1.currency != 'EUR' 
       THEN fms1.amount * fms1.rate 
      ELSE ISNULL(fms1.amount, 0) END) fmsTotalAmountOutgoing 
    FROM [fms].[dbo].[file] f 
     INNER JOIN [fms].[dbo].[outgoinginvoiceline] fms1 ON 
     fms1.filenumber = CONVERT(NVARCHAR, f.filenumber) 
    WHERE f.RELATIONCODE = @RelationCode 
    ) a 
    SET @IncomingInvoice = (SELECT fmsTotalAmountIncoming FROM [fms].[dbo].[TempIncomingAmounts]) 
     SET @OutgoingInvoice = (SELECT fmsTotalAmountOutgoing FROM [fms].[dbo].[TempOutgoingAmounts]) 
     SET @Profit = ((@OutgoingInvoice - @IncomingInvoice)/@OutgoingInvoice) 

     INSERT INTO @RESULTTABLE ([RELATIONCODE], [CompanyName], [IncomingInvoice], [OutgoingInvoice], [Profit]) 
       VALUES (@RelationCode, @CompanyName, @IncomingInvoice, @OutgoingInvoice, @Profit) 

     DROP TABLE [fms].[dbo].[TempIncomingAmounts] 
     DROP TABLE [fms].[dbo].[TempOutgoingAmounts] 

     DELETE FROM @RelationTable WHERE RelationCode = @RelationCode 
    END 

    SELECT * FROM @RESULTTABLE 

我已經基準這一點，下面的結果：

STORED PROCEDURE  VB.NET 
6:54     5:11 
6:20     5:11 
6:19     3:55 
6:43     4:01 

有沒有人對如何提高VB.net上述性能的任何線索性能，因爲這種方式存儲過程是沒用的。

Answer 1

您試圖在SQL中複製過程式VB代碼。 SQL是基於集合的，並且僅在此基礎上執行良好。不知道你的模式是什麼，這是大概你的SQL應該像讓你需要多大的成果，更快：

; 
WITH invoice (RELATIONCODE, COMPANYNAME, IncomingInvoice, OutgoingInvoice) 
AS (
    SELECT r.[RELATIONCODE], r.[COMPANYNAME], 
    SUM(CASE WHEN fms1.currency != 'EUR' 
      THEN fms1.amount * fms1.rate 
     ELSE ISNULL(fms1.amount, 0) END) AS IncomingInvoice, 
    SUM(CASE WHEN fmso.currency != 'EUR' 
      THEN fmso.amount * fmso.rate 
     ELSE ISNULL(fmso.amount, 0) END) AS OutgoingInvoice 
    FROM [fms].[dbo].[Relation] r 
    LEFT OUTER JOIN [fms].[dbo].[file] f 
    ON f.RELATIONCODE = r.[RELATIONCODE] 
    LEFT OUTER JOIN [fms].[dbo].[incominginvoiceline] fms1 
    ON fms1.filenumber = CONVERT(NVARCHAR, f.filenumber) 
    LEFT OUTER JOIN [fms].[dbo].[outgoinginvoiceline] fmso 
    ON fmso.filenumber = CONVERT(NVARCHAR, f.filenumber) 
    GROUP BY r.[RELATIONCODE], r.[COMPANYNAME] 
) 
SELECT RELATIONCODE, 
    COMPANYNAME, 
    IncomingInvoice, 
    OutgoingInvoice, 
    CASE WHEN OutgoingInvoice > 0 THEN (OutgoingInvoice - IncomingInvoice)/OutgoingInvoice 
    ELSE 0 END AS Profit 
FROM invoice 

即沒有循環，if ... else語句，創建，刪除然後重新創建永久表等等。只需要一個SQL語句按關係代碼和公司名稱對結果進行分組。