Restrict the max depth of plan tree in optimizer #5050
Merged
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What type of PR is this?
What problem(s) does this PR solve?
Issue(s) number:
Fix #4982.
Related https://github.com/vesoft-inc/nebula-ent/issues/1487.
Description:
In most cases, we can considier to constrict the depth of the plan tree to avoid stack overflow crash caused by some bad queries.
But for some queries such as
statement1 interest statement2 interest statement3 ...
,which is a very normal statement, even if there are many statements to intersect,
we may need to consider the multi-way operator in planner to avoid the overflow.
e.g.
The binary intersect operator:
The multi-way intersect operator:
How do you solve it?
Special notes for your reviewer, ex. impact of this fix, design document, etc:
Checklist:
Tests:
Affects:
Release notes:
Please confirm whether to be reflected in release notes and how to describe: