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Changes between Initial Version and Version 1 of Ticket #472, comment 5

initial	v1
	1	//edit: The code given below is of course specialised for multipolygons and I just figured it does not work for empty geometries (throws rather cryptic error).
	2
1	3	This is how I handle geography validity atm. Being aware that this may be resource intensive and that it may still fail e.g. if the object was projected in an st_intersect (where the best_srid is created for both objects together, afaik) with the respective documentation this might actually help some users. Be aware though that casting between geog and geom may introduce errors at a later stage. E.g. st_difference on two valid geoms casted to geog may produce invalid geogs when the resulting geom is casted back.
2	4