feat(optimizer): Implement naive join ordering #3616
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
CodSpeed Performance ReportMerging #3616 will not alter performanceComparing Summary
|
Codecov ReportAttention: Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #3616 +/- ##
==========================================
+ Coverage 77.69% 77.93% +0.23%
==========================================
Files 710 720 +10
Lines 86896 88728 +1832
==========================================
+ Hits 67513 69149 +1636
- Misses 19383 19579 +196
|
samster25
approved these changes
Dec 20, 2024
| #[derive(Clone, Debug)] | ||
| pub(super) enum JoinOrderTree { | ||
| Relation(usize), // (id). | ||
| Join(Box<JoinOrderTree>, Box<JoinOrderTree>, Vec<usize>), // (subtree, subtree, nodes involved). |
There was a problem hiding this comment.
instead of the nodes involved, you can implement Iterator to give you the nodes involved.
impl Iterator for JoinOrderTree {
...
}
There was a problem hiding this comment.
Sounds good! I opted for JoinOrderTree.iter() -> JoinOrderTreeIterator which then implements Iterator by maintaining a stack of Joins/Relations.
src/daft-logical-plan/src/optimization/rules/reorder_joins/join_graph.rs
Outdated
Show resolved
Hide resolved
src/daft-logical-plan/src/optimization/rules/reorder_joins/join_graph.rs
Outdated
Show resolved
Hide resolved
src/daft-logical-plan/src/optimization/rules/reorder_joins/naive_join_order.rs
Outdated
Show resolved
Hide resolved
src/daft-logical-plan/src/optimization/rules/reorder_joins/naive_join_order.rs
Outdated
Show resolved
Hide resolved
src/daft-logical-plan/src/optimization/rules/reorder_joins/join_graph.rs
Show resolved
Hide resolved
desmondcheongzx
added a commit
that referenced
this pull request
Jan 6, 2025
Missed a comment to #3616 (comment): ``` In [src/daft-logical-plan/src/optimization/rules/reorder_joins/join_graph.rs](#3616 (comment)): > }; -#[derive(Debug)] -struct JoinNode { +// TODO(desmond): In the future these trees should keep track of current cost estimates. +#[derive(Clone, Debug)] +pub(super) enum JoinOrderTree { + Relation(usize), // (id). + Join(Box<JoinOrderTree>, Box<JoinOrderTree>, Vec<usize>), // (subtree, subtree, nodes involved). I dont think you need to keep an explicit stack. I think you should be able to something like std::iter::chain(left.into_iter(), right.into_iter()) ``` This PR removes the stack and simply chains the iterators.
desmondcheongzx
added a commit
that referenced
this pull request
Jan 8, 2025
Applies the naive left deep join order from #3616 as an optimizer rule. This optimizer rule is gated behind an environment variable that allows us to validate the rule on our current workloads. Currently join reordering results in errors for 50% of TPC-H queries during join graph building. We'll tackle these in a follow-up PR.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Implements a naive join orderer that simply takes joins relations arbitrarily (as long as a valid join condition exists).
This is intended as a building block to ensure that our join graphs can correctly reconstruct into logical plans. The PR that will immediately follow this will create an optimization rule that applies naive join ordering. The optimization rule will be hidden behind a config flag, but will allow us to test logical plan reconstruction on all our integration tests.