实体框架抛出错误:
Test 'WorkerProcessService.Test.WorkerProcessMonitorTests.Test' failed: System.Data.UpdateException : Unable to update the EntitySet 'Processor' because it has a DefiningQuery and no <InsertFunction> element exists in the <ModificationFunctionMapping> element to support the current operation.
at System.Data.SqlClient.SqlGen.DmlSqlGenerator.ExpressionTranslator.Visit(DbScanExpression expression)
at System.Data.Common.CommandTrees.DbScanExpression.Accept(DbExpressionVisitor visitor)
at System.Data.SqlClient.SqlGen.DmlSqlGenerator.GenerateInsertSql(DbInsertCommandTree tree, SqlVersion sqlVersion, List`1& parameters)
at System.Data.SqlClient.SqlGen.SqlGenerator.GenerateSql(DbCommandTree tree, SqlVersion sqlVersion, List`1& parameters, CommandType& commandType, HashSet`1& paramsToForceNonUnicode)
at System.Data.SqlClient.SqlProviderServices.CreateCommand(DbProviderManifest providerManifest, DbCommandTree commandTree)
at System.Data.SqlClient.SqlProviderServices.CreateCommand(DbCommandTree commandTree)
at System.Data.Mapping.Update.Internal.UpdateTranslator.CreateCommand(DbModificationCommandTree commandTree)
at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.CreateCommand(UpdateTranslator translator, Dictionary`2 identifierValues)
at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator translator, EntityConnection connection, Dictionary`2 identifierValues, List`1 generatedValues)
at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
at System.Data.EntityClient.EntityAdapter.Update(IEntityStateManager entityCache)
at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options)
at System.Data.Objects.ObjectContext.SaveChanges()
WorkerProcessMonitor.cs(79,0): at Star.Portal.Services.WorkerProcessMonitor.AddComponent(Byte[] component)
WorkerProcessMonitorTests.cs(55,0): at WorkerProcessService.Test.WorkerProcessMonitorTests.Test()
我有一个表格,并且自动生成了edmx模型
CREATE TABLE [dbo].[Processor](
[ProcessorID] [int] IDENTITY(1,1) NOT NULL,
[ProcessorDLL] [varbinary](max) NULL,
)
以下内容无法更新
public void AddComponent(byte[] component)
{
Processor p = new Processor()
{
ProcessorDLL = component,
};
using (var cn = GetWorkerProcessEntities())
{
cn.AddToProcessors(p);
cn.SaveChanges();
}
}
问题是:我是否必须做任何特定的事情来在sql server中实现二进制存储?
答案 0 :(得分:1)
简单回答...不,我将图像存储在具有相同数据类型(varbinary(max))的表中。
对代码不太了解,我使用本地数据库进行简单测试。 这是我的POCO和DBcontext。 (我不使用自动生成的edmx)
using System.Data.Entity.ModelConfiguration;
public class Processor
{
public int ProcessorId { get; set; }
public byte[] ProcessorDLL { get; set; }
}
public class ProcessorConfiguration : EntityTypeConfiguration<Processor>
{
public ProcessorConfiguration()
{
HasKey(i => i.ProcessorId);
ToTable("Processor", "dbo");
}
}
//DbContext
public class myContext : DbContext
{
public DbSet<Processor> Processors { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Configurations.Add(new ProcessorConfiguration());
base.OnModelCreating(modelBuilder);
}
}
然后当我添加一个新的处理器时,我使用这个
public void test()
{
myContext context = new myContext();
Processor p = new Processor
{
ProcessorDLL = getSomeRandomByteArray()
};
context.Processors.Add(p);
context.SaveChanges();
}
在我的表格中:
ProcessorID: 1
ProcessorDLL: 0xFFD8FFE000104A46494600010200...
希望这会有所帮助。