如何在Entity Framework 4.1中使用IsNull映射具有列数据类型int的表 [英] How to map the Table having column data type int with IsNull in Entity Framework 4.1

问题描述

大家好，

我在Entity Framework 4.1中遇到了表映射的一个问题.
我有一个表名称Promotion，具有列intDeletedBy和datDeletedOn
而且我只想从数据库中获取未删除的记录

但是当我将带有实体框架的表映射为intDeletedBy列或datDeletedOn
我在条件标签上收到一条错误消息

Hello All,

I am facing one issue with Table Mapping in Entity Framework 4.1.
I have a table name Promotion having column intDeletedBy and datDeletedOn
and i want to fetch only those records from DB which are not deleted

but when i map the table with entity frame work for the column intDeletedBy or datDeletedOn
i am getting an error message on the condition tag

报价:

错误3032:映射片段的问题从第261行开始:条件成员"CMS_Promotion.datDeletedOn"的条件不是'' IsNull = False''已映射.删除CMS_Promotion.datDeletedOn上的条件，或将其从映射中删除.

Error 3032: Problem in mapping fragments starting at line 261:Condition member ''CMS_Promotion.datDeletedOn'' with a condition other than ''IsNull=False'' is mapped. Either remove the condition on CMS_Promotion.datDeletedOn or remove it from the mapping.

我的xml代码在C-S映射内容中

my xml code is in C-S mapping content

<EntitySetMapping Name="Promotions">
           <EntityTypeMapping TypeName="Lorenz_dataModel.Promotion">
             <MappingFragment StoreEntitySet="CMS_Promotion">
               <ScalarProperty Name="PromotionId" ColumnName="autPromotionId" />
               <ScalarProperty Name="Name" ColumnName="vchName" />
               <ScalarProperty Name="Description" ColumnName="vchDescription" />
               <ScalarProperty Name="ValidFrom" ColumnName="datValidFrom" />
               <ScalarProperty Name="ValidTo" ColumnName="datValidTo" />
               <ScalarProperty Name="CreatedBy" ColumnName="intCreatedBy" />
               <ScalarProperty Name="CreatedOn" ColumnName="datCreatedOn" />
               <ScalarProperty Name="ModifiedBy" ColumnName="intModifiedBy" />
               <ScalarProperty Name="ModifiedOn" ColumnName="datModifiedOn" />
               <ScalarProperty Name="DeletedBy" ColumnName="intDeletedBy" />
               <ScalarProperty Name="DeletedOn" ColumnName="datDeletedOn" />
               <Condition ColumnName="datDeletedOn" IsNull="true"/>
             </MappingFragment>
           </EntityTypeMapping>
         </EntitySetMapping>

请建议我如何克服这个问题.
我不想更改数据库表的数据类型

等待回复
谢谢

pls suggest me how can i overcome from this issue.
I dont want to change the datatype of my db table

waiting for reply
Thanks

推荐答案

您可以为期望为空的列声明数据类型为可空

请参考此参考 [

you can declare datatype as nullable for columns you expect to be null

please refer this as reference[^] for same.

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