使用LINQ查询过滤，但它正在选择特定的密钥很多次 [英] Using LINQ Query to Filter but it is selecting the particular Key Numerous times

问题描述

大家好我正在尝试使用LINQ to SQL从表（_dtlayout）查询。我正在尝试选择列名FK_DataPoint。

但是当我调试它时，它会多次击中该列。它不会引起任何错误，但对性能而言，它是一个主要问题。我知道我正在使用Where子句，它会遍历每一行并过滤它。但有没有更好的方法将此代码放在一起以过滤此DATAPOINT列。谢谢 。

Hi all i am trying to Query from a table (_dtlayout) using the LINQ to SQL. I am trying to select a column name FK_DataPoint.
But when i Debug it out it is hitting that column numerous times. It does not throw any ERROR but for Performance wise it is a major issue. I know i am using a Where clause which goes to each rows and filters it. But is there a better way to put this code together in order to filter this DATAPOINT Column. Thank you .

int? dataPointKey = _dtLayout.AsEnumerable().
    Where(row => row.Field<int?>("FK_FinancialStatementTemplateSectionItem") 
== colDef.FK_FinancialStatementTemplateSectionItem 
&& row.Field<int?>("RowNumber") == columnItem.RowNumber
&& row.Field<int?>("ColumnNumber") == colDef.ColumnNumber
&& row.Field<int?>("ItemNumber") == columnItem.ItemNumber)                                
.Select (row =>row.Field<int?>("FK_DataPoint")).FirstOrDefault();

谢谢

Thanks

推荐答案

您正在使用单个查询。使用f11键，所以如果你使用f10就会多次击中它会在几分之一秒内执行。因此不存在更大的性能问题。

You are using a single query. U r using f11 key and so it is hitting many times if u use f10 it'll execute with in a fraction of seconds.So there will be no bigger performance issue.

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