Definition
Action type for a timeline def~timeline-instant
| Excerpt |
|---|
COMMITS - `action type` which denotes an atomic write of a batch of records from an external source into a dataset def~dataset (see commit def~commit).CLEANS - `action type` which denotes a background activity that gets rid of older versions of files in the dataset def~dataset, that are no longer needed.DELTA_COMMIT - `action type` which denotes an atomic write of a batch of records into a Merge On Read (MOR) storage def~merge-on-read def~storage-type of dataset def~dataset, where some/all of the data could be just written to delta logs (see commit def~commit).COMPACTION - `action type` which denotes a background activity to reconcile differential data structures within Hudi e.g: moving updates from row based delta log files to columnar file formats. Internally, compaction manifests as a special commit def~commit on the timeline (see timeline def~timeline-instant)ROLLBACK - `action type` denotes that a timeline def~timeline-instant of `instant action type` commit/delta commit was unsuccessful & rolled back, removing any partial files produced during such a writeSAVEPOINT - `action type` marks certain file groups as “saved”, such that cleaner will not delete them. It helps restore the dataset def~dataset to a point on the timeline, in case of disaster/data recovery scenarios.
|
Related concepts
- timeline def~timeline-instant
- instant action typeinstant state
- instant time
- datasetdef~dataset
- commitdef~commit