为什么 SQL Where 子句值是由用户提供还是嵌入在代码中很重要？

Question

我有一个按设计工作的遗留 SSRS 报告 - returns 大量数据。

我创建了它的一个推导，旨在使用特定值。

IOW，在旧报表中，该值由用户选择，而在派生报表中，它是 "baked in."

派生的报告，经过多次沙漏和仓鼠笼的嘎嘎声，终于举起双手说，"An error occurred during local report processing. The size necessary to buffer the XML content exceeded the buffer quota."

一个相关的问题是 here。

两份报告的唯一区别是：

1) 我删除了其中一个参数

2) 在引用该参数的地方，我用文字值替换了 .rdl 中的代码。

为什么该更改会导致报告继续strike/go擅离职守？

更具体地说，以下是旧报告和派生报告之间的唯一区别：

1) 遗产：

<DataSetName>CPSData</DataSetName>

新：

<DataSetName>DataSetOldChicago</DataSetName>

2) 遗产：

<Value>=Parameters!Unit.value+", For Price Period: "+Parameters!BegDate.value+" - "+Parameters!EndDate.value</Value>

新：

<Value>="For Price Period: "+Parameters!BegDate.value+" - "+Parameters!EndDate.value</Value>

3) 遗产：

<DataSet Name="CPSData">
  <Query>
    <DataSourceName>CPSData</DataSourceName>
    <QueryParameters>
      <QueryParameter Name="@Unit">
        <Value>=Parameters!Unit.Value</Value>
      </QueryParameter>
      <QueryParameter Name="@BegDate">
        <Value>=Parameters!BegDate.Value</Value>
      </QueryParameter>
      <QueryParameter Name="@EndDate">
        <Value>=Parameters!EndDate.Value</Value>
      </QueryParameter>
      <QueryParameter Name="@SortBy">
        <Value>="Products"</Value>
      </QueryParameter>
    </QueryParameters>
    <CommandType>StoredProcedure</CommandType>
    <CommandText>sp_ViewPriceMatrix_Variance_RockBottom</CommandText>
    <rd:UseGenericDesigner>true</rd:UseGenericDesigner>
  </Query>

新：

<DataSet Name="DataSetOldChicago">
  <Query>
    <DataSourceName>CPSData</DataSourceName>
    <QueryParameters>
      <QueryParameter Name="@BegDate">
        <Value>=Parameters!BegDate.Value</Value>
      </QueryParameter>
      <QueryParameter Name="@EndDate">
        <Value>=Parameters!EndDate.Value</Value>
      </QueryParameter>
      <QueryParameter Name="@SortBy">
        <Value>=Parameters!SortBy.Value</Value>
      </QueryParameter>
    </QueryParameters>
    <CommandType>StoredProcedure</CommandType>
    <CommandText>ViewPriceMatrix_CraftworksRollup_OldChicago</CommandText>
  </Query>

所以新的缺少"Unit"参数；之后，将显示字段，除了

出于某种原因，顺序略有不同 - 我不知道为什么会这样，但无法想象这会导致问题（字段列出的顺序）。

4) 遗产：

<DataSet Name="UnitDS">
  <Query>
    <DataSourceName>CPSData</DataSourceName>
    <CommandText>select Unit from MasterUnits order by Unit</CommandText>
    <rd:UseGenericDesigner>true</rd:UseGenericDesigner>
  </Query>
  <Fields>
    <Field Name="Unit">
      <DataField>Unit</DataField>
      <rd:TypeName>System.String</rd:TypeName>
    </Field>
  </Fields>
</DataSet>

新：

缺失，因为用户不再选择单位

5) 遗产：

<ReportParameter Name="Unit">
  <DataType>String</DataType>
  <AllowBlank>true</AllowBlank>
  <Prompt>Unit</Prompt>
  <ValidValues>
    <DataSetReference>
      <DataSetName>UnitDS</DataSetName>
      <ValueField>Unit</ValueField>
      <LabelField>Unit</LabelField>
    </DataSetReference>
  </ValidValues>
</ReportParameter>

新：

缺失 - 现在按字面提供。

6) 遗产：

[这里什么都没有]

新：

<ReportParameter Name="SortBy">
  <DataType>String</DataType>
  <Prompt>Sort By</Prompt>
</ReportParameter>

-- 所以 new/non-working 报告有这个 "SortBy" 参数，它是隐藏的并提供了一个默认值。但是另一个派生报告以这种方式设置了相同的参数，不会造成任何问题。

关于为什么这个问题会出现食人魔般的面貌，有什么想法吗？

更新

旧的（工作的）SP 和派生的（非工作的）SP 之间的区别是：

1)

旧：

ALTER Procedure [dbo].[sp_ViewPriceMatrix_Variance_test2]
    @Unit varchar(4000),
    @BegDate datetime,
    @EndDate datetime,
    @SortBy varchar(20)

新：

IF OBJECT_ID ( 'ViewPriceMatrix_CraftworksRollup_OldChicago', 'P' ) IS NOT NULL   
    DROP PROCEDURE ViewPriceMatrix_CraftworksRollup_OldChicago;  
GO
CREATE PROCEDURE [dbo].[ViewPriceMatrix_CraftworksRollup_OldChicago]
    @BegDate datetime,
    @EndDate datetime

2)

旧：

where up.Unit = @Unit

新：

where up.Unit = 'OLD CHICAGO'

3)

-同 2)

4)

旧：

Select @Statement = ('Update #TempContract Set [' + @PriceWeek  + ']=''' + IsNull(@Price,'0.00') + ''' where ItemCode=''' + @ItemCode + ''' and Unit=''' + @Unit + ''' and [ShortName]=''' + @ShortName +'''')

新：

Select @Statement = ('Update #TempContract Set [' + @PriceWeek  + ']=''' + IsNull(@Price,'0.00') + ''' where ItemCode=''' + @ItemCode + ''' and Unit=''''OLD CHICAGO'''' and [ShortName]=''' + @ShortName +'''')

5)

旧：

            fetch next from SetPriceWeekSQL into @PriceWeek, @BegDate
while @@fetch_status = 0
    begin
        SET @Week = @Week + 1 
        IF(@SQLstring='')
        Begin
            SET @SQLstring = @SQLstring + 'Insert Into #Temp Select Unit, ShortName, ItemCode, Description, regionorder, Contractprice, IsNull('+
            '['+@PriceWeek+'],''0.00'') as Price, (convert(decimal(10,3),''-0.001'')) as Variance, 
            '''+@PriceWeek+''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract'+@WherePriceWeek

            IF(@SortBy='Members')
            Begin
                SET @SQLstring = @SQLstring + ' UNION Select Unit, ShortName, '''', ''zzzz'', '''', '''', ''0'' as Price, ''-0.001'' as Variance, '''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract'+@WherePriceWeek
            End
            Else
            Begin
                SET @SQLstring = @SQLstring + ' UNION Select Unit, '''', ItemCode, Description, ''1000'', Contractprice, ''0'' as Price, ''-0.001'' as Variance, '''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract'+@WherePriceWeek
            End
        End
        ELSE 
        Begin
            SET @SQLstring = @SQLstring + ' UNION '
            SET @SQLstring = @SQLstring + 'Select Unit, ShortName, ItemCode, Description, regionorder, Contractprice, IsNull('+
            '['+@PriceWeek+'],''0.00'') as Price, IsNull(convert(decimal(10,2),['+@PriceWeek+'])-convert(decimal(10,2),['+@LastPriceWeek+']),''0.00'') as Variance, 
            '''+@PriceWeek+''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract'+@WherePriceWeek

            IF(@SortBy='Members')
            Begin
                SET @SQLstring = @SQLstring + ' UNION Select Unit, ShortName, '''', ''zzzz'', '''', '''', ''0'' as Price, ''0'' as Variance, '''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract Where IsNull(['+@LastPriceWeek+'],''0.00'') 
<> ''0.00'' or IsNull(['+@PriceWeek+'],''0.00'') <> ''0.00'' '
            End
            Else
            Begin
                SET @SQLstring = @SQLstring + ' UNION Select Unit, '''', ItemCode, Description, ''1000'', Contractprice, ''0'' as Price, ''0'' as Variance, '''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract Where IsNull(['+@LastPriceWeek+'],''0.00'') <> ''0.00'' or IsNull(['+@PriceWeek+'],''0.00'') <> ''0.00'' '
            End
        End

新：

fetch next from SetPriceWeekSQL into @PriceWeek, @BegDate
while @@fetch_status = 0
    begin
        SET @Week = @Week + 1 
        IF(@SQLstring='')
        Begin
            SET @SQLstring = @SQLstring + 'Insert Into #Temp Select Unit, ShortName, ItemCode, Description, regionorder, Contractprice, IsNull('+
            '['+@PriceWeek+'],''0.00'') as Price, (convert(decimal(10,3),''-0.001'')) as Variance, 
            '''+@PriceWeek+''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract'+@WherePriceWeek

                SET @SQLstring = @SQLstring + ' UNION Select Unit, '''', ItemCode, Description, ''1000'', Contractprice, ''0'' as Price, ''-0.001'' as Variance, '''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract'+@WherePriceWeek
        End
        ELSE 
        Begin
            SET @SQLstring = @SQLstring + ' UNION '
            SET @SQLstring = @SQLstring + 'Select Unit, ShortName, ItemCode, Description, regionorder, Contractprice, IsNull('+
            '['+@PriceWeek+'],''0.00'') as Price, IsNull(convert(decimal(10,2),['+@PriceWeek+'])-convert(decimal(10,2),['+@LastPriceWeek+']),''0.00'') as Variance, 
            '''+@PriceWeek+''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract'+@WherePriceWeek

                SET @SQLstring = @SQLstring + ' UNION Select Unit, '''', ItemCode, Description, ''1000'', Contractprice, ''0'' as Price, ''0'' as Variance, '''' as PriceWeek, ''WK'+convert(varchar(2),@Week)+''' as Week From #TempContract Where IsNull(['+@LastPriceWeek+'],''0.00'') <> ''0.00'' or IsNull(['+@PriceWeek+'],''0.00'') <> ''0.00'' '
        End
        SET @LastPriceWeek = @PriceWeek
        fetch next from SetPriceWeekSQL into @PriceWeek, @BegDate
    end

6)

旧：

IF(@SortBy='Members')
Begin
    Select 
        Unit,
        ShortName,
        ItemCode,
        Description,
        regionorder,
        Contractprice,
        convert(varchar(20),convert(decimal(10,2),Price)) as Price,
        sum(convert(money,Variance)) as Variance,
        VarianceAverage = convert(varchar(25),convert(decimal(10,2),(Select sum(convert(money,Variance)) From #Temp Where ShortName=T.ShortName and Week=T.Week) / Replace(((Select count(regionorder) From #Temp Where ShortName=T.ShortName and Week=T.Week)-count(
Variance)),'0','1'))), 
        PriceWeek,Week
    From #Temp T
    Group By
        Unit,
        ShortName,
        ItemCode,
        Description,
        regionorder,
        Contractprice,
        Price,
        PriceWeek,Week  
    Order By Week,ShortName,Description
End
ELSE
Begin
    Select 
        Unit,
        ShortName,
        ItemCode,
        Description,
        regionorder,
        Contractprice,
        convert(varchar(20),convert(decimal(10,2),Price)) as Price,
        sum(convert(money,Variance)) as Variance,
        VarianceAverage = convert(varchar(25),convert(decimal(10,2),(Select sum(convert(money,Variance)) From #Temp Where ItemCode=T.ItemCode and Week=T.Week) / Replace(((Select count(regionorder) From #Temp Where ItemCode=T.ItemCode and Week=T.Week)-count(Variance)),'0','1'))), 
        PriceWeek,Week
    From #Temp T 
    Group By
        Unit,
        ShortName,
        ItemCode,
        Description,
        regionorder,
        Contractprice,
        Price,
        PriceWeek,Week  
    Order By Week,Description,regionorder 
End

新：

 Select 
    Unit,
    ShortName,
    ItemCode,
    Description,
    regionorder,
    Contractprice,
    convert(varchar(20),convert(decimal(10,2),Price)) as Price,
    sum(convert(money,Variance)) as Variance,
    VarianceAverage = convert(varchar(25),convert(decimal(10,2),(Select sum(convert(money,Variance)) From #Temp Where ItemCode=T.ItemCode and Week=T.Week) / Replace(((Select count(regionorder) From #Temp Where ItemCode=T.ItemCode and Week=T.Week)-count(Variance)),'0','1'))), 
    PriceWeek,Week
From #Temp T 
Group By
    Unit,
    ShortName,
    ItemCode,
    Description,
    regionorder,
    Contractprice,
    Price,
    PriceWeek,Week  
Order By Week,Description,regionorder

Answer 1

SQL 中的参数在确定特定语句的执行计划方面起着重要作用。例如，如果查询具有变量与硬编码文字，SQL 可能会为此创建两个完全不同的计划。 WHERE 子句中搜索参数的 addition/removal 也很可能会导致使用的索引发生更改。同样，如果一个计划已经使用了很长时间然后你改变了它，即使是轻微的改变，它现在也需要通过构建新计划、优化它、缓存它（如果可行）等的额外开销......

简而言之，这个看似很小的更改很可能完全改变了您的执行计划。就性能而言，这可能会产生各种意想不到的结果。我会推荐运行你的两个不同版本，所有输出 (PRINT/SELECTs) 都被删除（我希望这会降低内存使用率并允许你的第二个版本完成？）并看看你是否可以捕获实际执行计划。它可能会阐明它所做的不同之处，以及为什么它会突然停滞不前并最终失败。

Answer 2

您似乎在调用两个完全独立的存储过程 sp_ViewPriceMatrix_Variance_RockBottom 和 ViewPriceMatrix_CraftworksRollup_OldChicago。无论您在 SSRS 定义中进行了何种更改，您都需要查看基础数据查询之间的差异。我怀疑他们有很大的不同。

为什么 SQL Where 子句值是由用户提供还是嵌入在代码中很重要？

Why does it matter whether a SQL Where clause value is provided by the user or embedded in the code matter?

tsql

sql-server

stored-procedures

rdl

reporting-services

更新