I was trying to figure out why subclassing is not based in a free where clause instead of discriminator column. Noboy ever thinked on it ? Or it involves too many complications ? This would apply to <any> collections too, instead of discriminator column (or worse documented UserTypes, god knows how it works, and it still bounded to the columns of just one table. I can't check class in a joined table).
Suppouse that my "classification" is based upon an "exists" query... There is no way to map it.

Thanks for the high level of this forum.

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