Shards
- Shard is a horizontal partition of a database or a search engine
- Term is not unique to InfluxDb and is possibly the corner stone of distributed databases design
- InfluxDB stores data in shard groups organized by retention policy to store data by time range
- Length of that time interval is shard group duration for auto-purge purposes
- Default shard group duration based on retention policy:
| RP Duration | Shard Group Duration |
|---|---|
| < 2 days | 1 hour |
| >= 2 days and <= 6 months | 1 day |
| > 6 months | 7 days |
