New Entity and IsDirty.
Joined: 09-Aug-2004
lethologica wrote:
If an entity is new, should it also be dirty?
If you create an new entity, and call save with out modifing any field, then the save will fail, and a new entity won't be created in the database.
A new entity is not called dirty because it doesn't have any data yet so there is nothing to save. It's perhaps a bit abstract, but teh entity INSTANCE you have in memory is the container of the actually entity, which is the data inside the instance (and also inside the record in the database). This means that if you create a new entity instance, you just create a new entity container without any data, so as there is nothing, nothing can be saved as well, so that's why it's not dirty but new 
Joined: 09-Aug-2004
lethologica wrote:
This makes sense, but if you want to insert an empty entity, then you have to make the entity dirty so it will save.
No, you have to set fields to values If you set just the isdirty flag it will not save (at least not on sqlserver)
What I am doing is inserting an entity, getting its ID, then passing that somewhere else so ir can be updated from there. Kinda silly, but that is what the spec calls for. So in order to do this, I have to make some field of the entity dirty.
Its no hassle in reality, but I just wanted to get your thoughts on why it was designed this way.
Saving an empty entity with just an identity field will result in a query like: INSERT INTO table () VALUES () as there are no fields set to a value. So you have to set a field to a value.