OpenTenBase / OpenTenBase/TXSQL
Add WinMagic Subquery Decorrelation
Nobody has claimed this yet.
- Dominant language
- C++
- Stars
- 337
- Forks
- 234
- PR merge metrics
- No merged PRs in 30d
Description
Some correlated scalar subqueries repeatedly access tables that are already referenced by the outer query block, which can lead to unnecessary execution overhead.
Add WinMagic optimization to decorrelate eligible correlated scalar subqueries using window functions. This optimization reduces redundant access to tables shared by the outer query and subquery, allowing supported queries to be transformed into a window aggregation plan for better execution performance.
Contributor guide
No contributing guide indexed for this repository
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 optimizer entry point for correlated scalar subqueries and any existing window-aggregation transformations. Verify the behavior with representative eligible queries; done means supported correlated scalar subqueries are decorrelated into window aggregation plans without changing their results.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- databases, performance
- Issue type
- Feature
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Quiet
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100