lance-format / lance-format/lance
Pushdown scanner not working with is null and large_binary
Open
Nobody has claimed this yet.
enhancement
- Dominant language
- Rust
- Stars
- 7.1k
- Forks
- 852
- Avg merge
- 3d 18h
- Merged PRs (30d)
- 272
Description
Given the query: large_binary_field IS NULL we are not getting a plan with pushdown and this query seems quite slow even though there are many fragments where large_binary_field is NULL in every row.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by locating the pushdown scanner and the handling for IS NULL on large_binary fields. Reproduce the query large_binary_field IS NULL, inspect its plan, and compare it with fragments where the field is always NULL. Done means the query receives an appropriate pushdown plan and avoids the reported slowdown.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- databases
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 35/100