prestodb/presto

Use @TypeParameter to simplify multimap_agg aggregation function

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#21,364 opened on Nov 10, 2023

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 (1 comment) (0 reactions) (1 assignee)Java (5,240 forks)batch import
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Description

With the merge of #21316 we can now simplify this aggregation function implementation by using @TypeParameter annotations in the serializer and state factory constructors, which means the function can be entirely converted to using the function annotation framework. This will simplify the implementation and improve maintainability.

Contributor guide

Research direction
Study the @TypeParameter annotation usage from #21316 and apply it to the multimap agg function's serializer and state factory constructors, replacing manual type handling.
Tech stack
java
Domain
backend
Issue type
Refactor
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaPresto function annotation framework
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65