I had a reference field, wich was Nullable, then i change it to Not Nullabe, Now during schema upgrade this:

exec sp_rename '[dbo].[DocumentOperation].[Entity_Id]', 'TempEntity_Id', 'COLUMN';
ALTER TABLE [dbo].[DocumentOperation] ADD [Entity_Id] uniqueidentifier DEFAULT '00000000-0000-0000-0000-000000000000' NOT NULL;
CREATE INDEX [DocumentOperation_FK_Entity] ON [dbo].[DocumentOperation] ([Entity_Id] ASC);
ALTER TABLE [dbo].[DocumentOperation] ADD CONSTRAINT [FK_DocumentOperation-Entity-DocEntity_Entity] FOREIGN KEY ([Entity_Id]) REFERENCES [dbo].[DocEntity] ([Id]);

This sql misses this statement:

UPDATE dbo.DocumentOperation SET Entity_Id = TempEnity_Id; Therefore the latter ALTER fails(Entity_Id is filled with zero guids)

Updated at 26.07.2010 6:28:27

This is the whole SQL text from the exception. I cannot reproduce this once more because I've fixed it manually

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