Bug #70888 NullReferenceException when try to save entity with TINYINT or BIGINT as PK
Submitted: 12 Nov 2013 11:21 Modified: 14 Dec 2013 0:43
Reporter: Der Meister Email Updates:
Status: Closed Impact on me:
None 
Category:Connector / NET Severity:S1 (Critical)
Version:6.7.4 OS:Microsoft Windows (7 x64)
Assigned to: Fernando Gonzalez.Sanchez CPU Architecture:Any
Tags: BIGINT, exception, NullReferenceException, Tinyint, UNSIGNED

[12 Nov 2013 11:21] Der Meister
Description:
I use MySql.Data.Entities 6.7.4 and try to save an entity into a table with bigint auto-incremented primary key. Connector/Net throws an exception:

System.NullReferenceException: Object reference not set to an instance of an object
   in MySql.Data.Entity.ListFragment.WriteSql(StringBuilder sql)
   in MySql.Data.Entity.SelectStatement.WriteSql(StringBuilder sql)
   in MySql.Data.Entity.InsertStatement.WriteSql(StringBuilder sql)
   in MySql.Data.Entity.SqlFragment.ToString()
   in MySql.Data.Entity.InsertGenerator.GenerateSQL(DbCommandTree tree)
   in MySql.Data.MySqlClient.MySqlProviderServices.CreateDbCommandDefinition(DbProviderManifest providerManifest, DbCommandTree commandTree)
   in System.Data.Common.DbProviderServices.CreateCommandDefinition(DbCommandTree commandTree)
   in System.Data.Common.DbProviderServices.CreateCommand(DbCommandTree commandTree)
   in System.Data.Mapping.Update.Internal.UpdateTranslator.CreateCommand(DbModificationCommandTree commandTree)
   in System.Data.Mapping.Update.Internal.DynamicUpdateCommand.CreateCommand(UpdateTranslator translator, Dictionary`2 identifierValues)
   in System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator translator, EntityConnection connection, Dictionary`2 identifierValues, List`1 generatedValues)
   in System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
   in System.Data.EntityClient.EntityAdapter.Update(IEntityStateManager entityCache)
   in System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options)
   in System.Data.Entity.Internal.InternalContext.SaveChanges()
   in System.Data.Entity.Internal.LazyInternalContext.SaveChanges()
   in System.Data.Entity.DbContext.SaveChanges()

MySql.Data 6.5.4 does not have this bug. I copied sample from SO (http://stackoverflow.com/a/16254132/991267). Oware reproduced the issue in Connector 6.6.5.

How to repeat:
Sample table:

create table person(
    Id tinyint unsigned primary key auto_increment,
    Name varchar(30)
);

Sample code:

var context = new Entities();
Person p;
p = new Person();
p.Name = "Oware";
context.Persons.Add(p);
context.SaveChanges();
[12 Nov 2013 11:23] Der Meister
Possibly linked bug: http://bugs.mysql.com/bug.php?id=70602
[4 Dec 2013 21:04] Fernando Gonzalez.Sanchez
Posted by developer:
 

This fix for this bug will appear in Connector/NET 6.6.7, 6.7.5 and 6.8.2.

With the fix, there is no longer a null reference exception, and the save changes operation is completed correctly.
[14 Dec 2013 0:43] Daniel So
Added the following entry into the Connector/Net 6.6.7, 6.7.5. and 6.8.2 changelogs:

"Connector/Net threw a NullReferenceException when trying to save an entity into a table with a tinyint or bigint auto-incremented primary key."