mirror of https://github.com/apache/druid.git
961 B
961 B
| layout |
|---|
| doc_page |
Concepts and Terminology
- Aggregators: A mechanism for combining records during realtime incremental indexing, Hadoop batch indexing, and in queries.
- DataSource: A table-like view of data; specified in a "specFile" and in a query.
- Granularity: The time interval corresponding to aggregation by time.
- indexGranularity: specifies the granularity used to bucket timestamps within a segment.
- segmentGranularity: specifies the granularity of the segment, i.e. the amount of time a segment will represent
- Segment: A collection of (internal) records that are stored and processed together.
- Shard: A sub-partition of the data in a segment. It is possible to have multiple segments represent all data for a given segmentGranularity.
- specFile: is specification for services in JSON format; see Realtime and Batch-ingestion