I would like to retrieve the total number of incoming or outgoing edges of a given type to/from a vertex in OrientDB. The obvious method is to construct a query using count() and inE(MyEdgeType), outE(MyEdgeType), or bothE(MyEdgeType). However, I am concerned about time complexity; if this operation is O(N) rather than O(1), I might be better off storing the number in the database rather than using count() each time I need it, because I anticipate the number of edges in question becoming very large. I have searched the documentation, but it does not seem to list the time complexities of OrientDB's functions. Also, I am unsure of whether to use in/out/both or inE/outE/bothE; I presume the E versions will be faster, but depending on how OrientDB stores edges under the hood, that may be wrong.
Is counting the set of incoming/outgoing/both edges of a given type to/from a vertex a constant-time operation--and if not, what is its time complexity? To be most efficient, do I need to use inE/outE/bothE, or in/out/both? Or is there some other method entirely that I've missed?
In OrientDB this is O(1): inE()/outE()/bothE().size() with or without the edge label as parameter.