timeline instant

Definition

An item in the `Hudi` ingestion processing timeline

Design details

At its core, Hudi maintains a timeline of all actions performed on the dataset at different instants of time that helps provide instantaneous views of the dataset, while also efficiently supporting retrieval of data in the order of arrival. A Hudi `timeline instant` consists of the following components

• Instant action type: Type of action performed on the dataset
• Instant time : Instant time is typically a timestamp (e.g: 20190117010349), which monotonically increases in the order of action’s begin time.
• Instant state : current state of the instant

Hudi guarantees that the actions performed on the timeline are atomic & timeline consistent based on the instant time.

Key Instant action types performed include:

Any given instant can be in one of the following instant states:

Design decisions

1. #todo

Related concepts

1. file format
2. commit

Status (draft)