MS SQL - 查询运行时间太长

Question

我有一个数据库触发器,而不是运行存储过程.

每次将新数据插入表时,此触发器都会运行.

这是存储过程查询:

编辑:新查询

declare @transaction_type int
set @transaction_type = (select  TransTyp from inserted)


declare @transaction_ctr bigint
set @transaction_ctr = (select TransCtr from inserted)

declare @transaction_no nvarchar(15)
set @transaction_no = (select TransNum from inserted)

declare @transaction_date datetime
set @transaction_date = (select TransDt from inserted)

declare @customer_code nvarchar(10)
set @customer_code = (select CustCode from inserted)

declare @contact nvarchar(15)
set @contact = (select CellNum  from inserted)


declare @transaction_info nvarchar(130)
set	@transaction_info = (select TransInfo from inserted)


declare @date_received datetime
set	@date_received = (select DtRcv from inserted)

declare @is_active int
set @is_active= (select	IsActive
				 from	BigESentData.dbo.tbl_sentRegistration
				 where CellNum = @contact)

declare @value nvarchar(130)
declare @pos int
declare @len int

if @is_active= 0 OR @is_active is null
begin
	delete from BigESentData.dbo.tbl_sentTransaction where TransCtr = @transaction_ctr
end

else
begin
	--exec parseSentData @transType

	/** Inventory */
	if @transaction_type = 3
	begin
		if not exists(select TransCtr from BigEMerchandiser.dbo.tbl_Inventory_H where TransCtr = @transaction_ctr)
		begin
			insert into BigEMerchandiser.dbo.tbl_Inventory_H
			Values(@transaction_ctr,@customer_code, @date_received, @contact)

			set @pos = 0
			set @len = 0
				while charindex('-', @transaction_info, @pos + 1) > 0
				begin
					set @len = charindex('|', @transaction_info, @pos + 1) - @pos
					set @value = substring(@transaction_info, @pos, @len)
						insert into BigEMerchandiser.dbo.tbl_Inventory_D(TransCtr, Material, Qty, ExpDt)
						select	@transaction_ctr,
								ltrim(rtrim(left(@value, charindex('-', @value) - 1))) as Material,
								replace(substring(@value,charindex('-',@value),len(@value) - charindex('-', reverse(@value)) - charindex('-', @value) + 1),'-', '') as Qty,
								reverse(left(reverse(@value),charindex('-', reverse(@value)) - 1))as ExpDt
					set @pos = charindex('|', @transaction_info, @pos + @len) + 1
				end
		end		
	end
	
	/** Delivery */
	if @transaction_type = 2
	begin
		if not exists(select TransCtr from BigEMerchandiser.dbo.tbl_Delivery_H where TransCtr = @transaction_ctr)
		begin
			insert into BigEMerchandiser.dbo.tbl_Delivery_H
			Values(@transaction_ctr, @transaction_no, @transaction_date, @customer_code, @date_received, @contact)

			set @pos = 0
			set @len = 0
				while charindex('-', @transaction_info, @pos + 1) > 0
				begin
					set @len = charindex('|', @transaction_info, @pos + 1) - @pos
					set @value = substring(@transaction_info, @pos, @len)
						insert into BigEMerchandiser.dbo.tbl_Delivery_D(TransCtr, Material, Qty, ExpDt)
						select	@transaction_ctr,
								ltrim(rtrim(left(@value, charindex('-', @value) - 1))) as Material,
								replace(substring(@value,charindex('-',@value),len(@value) - charindex('-', reverse(@value)) - charindex('-', @value) + 1),'-', '') as Qty,
								reverse(left(reverse(@value),charindex('-', reverse(@value)) - 1))as ExpDt
					set @pos = charindex('|', @transaction_info, @pos + @len) + 1
				end
		end		
	end

	/** ABIS */
	if @transaction_type = 1
	begin
		if not exists(select TransCtr from BigEMerchandiser.dbo.tbl_Abis_H where TransCtr = @transaction_ctr)
		begin
			insert into BigEMerchandiser.dbo.tbl_Abis_H
			Values(@transaction_ctr, @transaction_no, @customer_code, @date_received, @contact)

			set @pos = 0
			set @len = 0
				while charindex('-', @transaction_info, @pos + 1) > 0
				begin
					set @len = charindex('|', @transaction_info, @pos + 1) - @pos
					set @value = substring(@transaction_info, @pos, @len)
						insert into BigEMerchandiser.dbo.tbl_Abis_D(TransCtr, Material, Qty, ExpDt)
						select	@transaction_ctr,
								ltrim(rtrim(left(@value, charindex('-', @value) - 1))) as Material,
								replace(substring(@value,charindex('-',@value),len(@value) - charindex('-', reverse(@value)) - charindex('-', @value) + 1),'-', '') as Qty,
								reverse(left(reverse(@value),charindex('-', reverse(@value)) - 1))as ExpDt
					set @pos = charindex('|', @transaction_info, @pos + @len) + 1
				end
		end		
	end

	/** end of transaction */
end

让我告诉你一个故事如何运行.数据来自Android应用程序.它是超市中商家的应用程序.该应用程序将数据转换为SMS并将数据发送到SQL数据库.

现在,如果将应用程序发送的数据插入数据库,则会触发触发器,并运行上面的存储过程.

存储过程按以下顺序运行:

1. 检查交易类型(在上面的查询中它是3,这是库存)

2. 检查tbl_sentdata中没有进入tbltransactionheader的所有记录,如果没有进入tbltransactionheader,请将其插入那里.

3. 检查tblsentdata中没有进入tbltransactiondetail的所有记录,解析分隔数据,并将每个记录插入一行.

tblsentdata - 来自应用程序的数据

tbltransactionheader - 标头表

tbltransactiondetail - 详细信息表

以下是应用程序的原始数据:

现在,正如您在屏幕截图中看到的那样,应用程序中的数据是分隔的.所以我需要逐个解析它.(在上面的查询中,解析从注释"/*Loop delimited data*/"开始)

现在,如果我手动运行存储过程,对于TransTyp 3(库存),则需要很长时间.

在我的猜测中,我上面的查询逐个检查来自tblsentdata的所有数据.所以如果我有100,000条记录,它每次都会检查它,即使数据已经在事务表上.

这是我的问题:

1. 我认为这是正确的吗？如果触发器触发,则运行查询.然后发送另一条文本消息,即使第一个查询未完成,触发器也会再次运行.然后发送另一条文本消息,触发器再次运行.

2. 我的查询是否是最佳方法？有没有办法更快？我负担不起运行这个查询需要花费很多时间.

希望你能赐教我,我是SQL查询的新手.或者至少引导我去哪里看.

希望我能很好地解释自己.我将不胜感激任何帮助和建议.谢谢.

更新:11/04/2018

感谢PSK.在他的帮助下,我能够解决我的问题并最小化查询中的while循环.我刚刚删除了存储过程.我直接从触发器运行查询,只选择插入的数据.

请参阅上面编辑过的查询.

感谢你们.

Answer 1

您应该避免WHILE在查询中使用，它会严重减慢您的查询速度。对于您的情况，您可以轻松避免 while 循环，这将提高查询的性能。

例如

现有代码

WHILE @headerCount > 0
BEGIN
    SET @transCtr = (SELECT TOP 1 TransCtr FROM BigESentData.dbo.tbl_sentTransaction WHERE TransCtr NOT IN (SELECT TransCtr FROM BigEMerchandiser.dbo.tbl_Inventory_H) and TransTyp = 3)

    IF NOT EXISTS(SELECT TransCtr FROM BigEMerchandiser.dbo.tbl_Inventory_H where TransCtr = @transCtr)
    BEGIN
        INSERT INTO BigEMerchandiser.dbo.tbl_Inventory_H
        SELECT TOP 1 TransCtr, CustCode, DtRcv, CellNum
        FROM BigESentData.dbo.tbl_sentTransaction where TransCtr = @transCtr
    END
    SET @headerCount = @headerCount - 1
END

修改（无 while）

 INSERT INTO BigEMerchandiser.dbo.tbl_Inventory_H
    SELECT TOP 1 TransCtr, CustCode, DtRcv, CellNum
    FROM BigESentData.dbo.tbl_sentTransaction A

    WHERE EXISTS
    (
        SELECT 1 FROM 
        BigESentData.dbo.tbl_sentTransaction T WHERE TransCtr NOT IN 
            (SELECT TransCtr FROM BigEMerchandiser.dbo.tbl_Inventory_H) and TransTyp = 3)
        AND T.TransCtr = A.TransCtr
    ) 

使用类似的方法，您可以实现第二个 while 循环。