19 Dec
2011
19 Dec
'11
8:52 a.m.
Hi, Stefan Manegold wrote:
Hi Viktor,
And my first guess with your Q8 and the inequality (self-?)join(?) is that this creates almost a Cartesian product of the one/two inputs, with large inputs, this can indeed become hugh ...
The self-join on node.id should not produce a big result, because it is restricted by an equality join on rank.parent. I.e. the pattern looks like this: rank1.parent = rank2.parent AND node1.id <> node2.id AND rank1.node_ref = node1.id AND rank2.node_ref = node2.id Cheers, Viktor