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Changes between Initial Version and Version 2 of Ticket #36748

initial	v2
36	36
37	37	I bumped into this regression when upgrading to 5.2 and the call to a Postgres extension function in such a placeholder, but which has a db_type that is present in self.connection.data_types, didn't happen anymore for bulk inserts.
	38
	39
	40	NB This bug can go unnoticed: bulk_create might succeed, but with different data written to disk than what is expected. And subsequent reads and seeks will have the wrong results.