[OAK-2341] Use approx counters property index costs even when path restriction is available - ASF JIRA

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Currently, cost calculation of property index follows following psuedo-code:

For "is not null" case:
1. return entryCount || approximate counted indexed nodes
2. if above doesn't work out, do a partial traversal and return extrapolated cost
For property in (a, b, ...) or property==value case:
1. return entryCount/keyCount || approximate counted index nodes for each key (a, b, etc)
2. if above doesn't work out, do a partial traversal over whole indexed tree or sub-tree (if path restriction is available) and return extrapolated cost

approx counter on index is used only if entryCount property is missing in index definition node.

The issue in step 1 in both cases is that it doesn't consider path restriction if it's given in the query.

The only place where path restriction is being considered is in case2->step2.

requires

OAK-1907 Better cost estimates for traversal, property, and ordered indexes