`DT[order(.), ...]` could create index on DT
Assessment
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Newbie friendliness
- 25/100
- Issue type
- Feature
- Clarity
- Mostly clear
- Activity status
- Stale
- Tech stack
- r
- Domain
- data, performance
Research direction
Start by reviewing linked pull request #4458 and issue #3023, then trace how order(.) invokes the expensive forder call for DT columns. Done means caching the forder result as an index only for eligible DT-column ordering cases, with proper na.last alignment.
Written by the indexing model from the issue text.
Description
As we already have to compute expensive forder call we could cache its results as index where possible. This would fit nicely together with https://github.com/Rdatatable/data.table/issues/3023
Of course not all cases of order should create index, but only those that order on DT columns, and having proper na.last alignment.
- Dominant language
- R
- Stars
- 3.9k
- Forks
- 1.1k
- Avg merge
- 14h 4m
- Merged PRs (30d)
- 4
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.
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