Details
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Improvement
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Status: Closed
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Major
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Resolution: Fixed
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1.1.3
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None
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None
Description
Currently, cost calculation of property index follows following psuedo-code:
- For "is not null" case:
- return entryCount || approximate counted indexed nodes
- if above doesn't work out, do a partial traversal and return extrapolated cost
- For property in (a, b, ...) or property==value case:
- return entryCount/keyCount || approximate counted index nodes for each key (a, b, etc)
- 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.
Attachments
Attachments
Issue Links
- requires
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OAK-1907 Better cost estimates for traversal, property, and ordered indexes
- Closed