小编fir*_*ude的帖子

我正在使用MySQL的Entity Framework,每次我尝试插入数据时它都会给我一个NullReferenceException.

• 我可以通过创建命令直接插入数据,但是当我使用Entity Framework时它就会爆炸.
• 实体框架将从表或更新表中进行选择,因此这可能与主键有关

从SaveChanges()方法抛出以下异常.

failed: System.NullReferenceException : Object reference not set to an instance of an object.
    at MySql.Data.Entity.ListFragment.WriteSql(StringBuilder sql)
    at MySql.Data.Entity.SelectStatement.WriteSql(StringBuilder sql)
    at MySql.Data.Entity.InsertStatement.WriteSql(StringBuilder sql)
    at MySql.Data.Entity.SqlFragment.ToString()
    at MySql.Data.Entity.InsertGenerator.GenerateSQL(DbCommandTree tree)
    at MySql.Data.MySqlClient.MySqlProviderServices.CreateDbCommandDefinition(DbProviderManifest providerManifest, DbCommandTree commandTree)
    at System.Data.Common.DbProviderServices.CreateCommandDefinition(DbCommandTree commandTree)
    at System.Data.Common.DbProviderServices.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()

EF 5

public decimal CreateAlertNotification2(ulong alertServiceId, …