DataFusion weekly project plan (Andrew Lamb) - Dec 25, 2023

[alamb]

Follow on to Dec 18 2023:

Boilerplate Overview

The idea of this ticket is make my plans for DataFusion visible, largely for my own personal organizational needs, but also to:

1. Try some different ways to communicate / coordinate in the community
2. Help provide an interesting summary of what is happening in DataFusion this week

It would be great if anyone else who has plans like this for DataFusion could try to make them visible somehow as well

My (personal) plans for this week

• Draft proposal to move DataFusion to a new top level apache project #8491
• Shepherd final Bloom Filter clean up PRs: Rewrite bloom filters to use contains API #8442

Project Queue (list of future projects)

• Blog post with DataFusion Jun - Sep 2023 #6780
• Epic: Statistics improvements #8227 (specifically, Introduce a way to represent constrained statistics / bounds on values in Statistics #8078)

Projects I hope to help review and coordinate

• Memory explosion in HashJoin outputs: HashJoinStream memory tracking insufficient #7848 from @korowa
• Making function packages more modular: [EPIC] Unify Function Interface (remove BuiltInScalarFunction) #8045
• Improve planning speed [Epic] A collection of issues to improve planning performance / speed / efficiency #5637 (e.g with benchmarks Benchmarks for planning queries #8638 )

Algorithm for (my) prioritizing PR reviews

Note there are many committers who can and review and merge PRs, so this is not the priorities of the project as a whole, just the approximate algorithm I am using

Priority:

1. Bug fixes (where something is just incorrect), especially regressions (where it used to work and now does not)
2. Improvements directly related to features needed for InfluxDB (my employer)
3. Documentation and test improvements (I view these as very strategically important)
4. PRs that I think are strategically important
5. Other new features / additions to functionality

The current strategically important projects in my head are:

• Making function packages modular and easier to mix/match: [EPIC] Unify Function Interface (remove BuiltInScalarFunction) #8045
• Improving performance of high cardinality aggregation (I have dreams of working on this over Christmas break)

Thus, if you are interested in contributing to DataFusion and are interested in a fast turn around time I would recommend looking into bug fixes / test improvements / documentation / etc.

If you propose adding new functionality, the review cycle will likely be longer. You can make it a shorter cycle by looking at the comments on other recent PRs and following the same model (e.g. ensure there are tests in sqllogictest for example, the CI passes, includes documentation, etc)

[alamb]

DataFusion

• Streaming CLI support #8651

[alamb]

DataFusion

• TreeNode Refactor Part 2 #8653
• feat: support inlist in LiteralGurantee for pruning #8654
• Add support for conflicting order sensitive aggregates in ARRAY_AGG aggregate function #8558

[alamb]

DataFusion

• Add schema_err! error macros with optional backtrace #8620 (review)
• Make the BatchSerializer behind Arc to avoid unnecessary struct creation #8666 (review)
• refactor: modified JoinHashMap build order for HashJoinStream #8658
• Start setting up tpch planning benchmarks #8665
• feat: support 'LargeList' in array_pop_front and array_pop_back #8569

[alamb]

DataFusion

• [pruning] Add shortcut when all units have been pruned #8675
• Implement the contained method of RowGroupPruningStatistics #8669
• Support Reading and Writing Extension FileTypes #8667
• Closes #8502: Parallel NDJSON file reading #8659

Arrow

• Add IPC FileDecoder arrow-rs#5249
• Default AWS region to us-east-1 (#5211) arrow-rs#5244

[alamb]

DataFusion

• Support for extract(epoch from date) for Date32 and Date64 #8695
• Cleanup TreeNode implementations #8672
• Change ScalarValue::{List, LargeList, FixedSizedList} to take specific types rather than ArrayRef #8562
• Convert Binary Operator StringConcat to Function for array_concat, array_append and array_prepend #8636
• Transform with payload #8664 (comment)
• Add support for recursive CTEs #7581
• Improve array_prepend signature for null and empty array #8625 (review)
• Improve array_concat signature for null and empty array #8594 (review)

SQLparser

• Support SQLite column definitions with no type datafusion-sqlparser-rs#1075
• Support MySQL FLUSH statement datafusion-sqlparser-rs#1076
• Add support for ENABLE and DISABLE on ALTER TABLE for pg datafusion-sqlparser-rs#1077
• Adds support for pg CREATE EXTENSION datafusion-sqlparser-rs#1078

Arrow

• Update docs for datatypes arrow-rs#5260
• Enhance temporal kernels for Time32/64 types arrow-rs#5262

[alamb]

Next up: #8704