Add aggreate key dependency optimizer

[andyfengHKU]

This PR adds AggregateKeyDependencyOptimizer which analyzes user input group by keys' dependency and split into keys and dependentKeys. A dependentKey has functional dependency on a key. keys will be hashed during hash aggregate while dependentKeys will be directly materialized into f-table.

Consider the following example

RETURN a.ID, a.age, COUNT(*)

Based on user input, both a.ID and a.age are stated as hash keys. However, since a.ID is the primary key, a.age has functional dependency on a.ID so we only need to hash a.ID in hash aggregate.

This optimizer is more important given Cypher grammar because the grammar itself doesn't differentiate SELECT and GROUP BY which means user cannot group by a subset of selection list. Another case is Cypher allows group by Node or Rel which by definition is to group by all properties of Node or Rel. A more reasonable solution is to only group by their internal IDs and treat properties as dependentKeys.

Performance benchmark

Dataset: LDBC100
Machine: M1 Pro, 16GB memory, maximum 4 threads
Query: MATCH (a:Person)-[:knows]->(b:Person) RETURN keys, COUNT(*) LIMIT 1; (Note that Aggregate is a Sink operator that is not affected by LIMIT, LIMIT 1 is to reduce print size).

Keys	Optimizer ON	Optimizer OFF
ID	207 ms	198 ms
ID, firstName	204 ms	292 ms
ID, firstName, lastName	214 ms	356 ms

[codecov]

Codecov Report

Patch coverage: 98.78% and project coverage change: +0.01 🎉

Comparison is base (bfc1b0d) 91.92% compared to head (1bd8063) 91.93%.

❗ Current head 1bd8063 differs from pull request most recent head 1aef377. Consider uploading reports for the commit 1aef377 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1517      +/-   ##
==========================================
+ Coverage   91.92%   91.93%   +0.01%     
==========================================
  Files         678      680       +2     
  Lines       24458    24528      +70     
==========================================
+ Hits        22482    22550      +68     
- Misses       1976     1978       +2     

Impacted Files	Coverage Δ
src/include/processor/mapper/plan_mapper.h	100.00% <ø> (ø)
src/planner/operator/logical_aggregate.cpp	97.67% <94.11%> (-2.33%)	⬇️
src/processor/mapper/map_aggregate.cpp	96.49% <96.42%> (-1.98%)	⬇️
...c/include/optimizer/agg_key_dependency_optimizer.h	100.00% <100.00%> (ø)
.../logical_plan/logical_operator/logical_aggregate.h	94.73% <100.00%> (-5.27%)	⬇️
...r/logical_plan/logical_operator/logical_distinct.h	94.44% <100.00%> (-5.56%)	⬇️
...rocessor/operator/aggregate/aggregate_hash_table.h	77.77% <100.00%> (ø)
...lude/processor/operator/aggregate/hash_aggregate.h	100.00% <100.00%> (ø)
src/optimizer/agg_key_dependency_optimizer.cpp	100.00% <100.00%> (ø)
src/optimizer/optimizer.cpp	100.00% <100.00%> (ø)
... and 5 more

... and 3 files with indirect coverage changes

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.