jihoonson commented on a change in pull request #6094: Introduce SystemSchema tables (#5989) URL: https://github.com/apache/incubator-druid/pull/6094#discussion_r223201454
########## File path: docs/content/querying/sql.md ########## @@ -528,6 +533,101 @@ SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'druid' AND TABLE_ |COLLATION_NAME|| |JDBC_TYPE|Type code from java.sql.Types (Druid extension)| +## SYSTEM SCHEMA + +The "sys" schema provides visibility into Druid segments, servers and tasks. +For example to retrieve all segments for datasource "wikipedia", use the query: +```sql +SELECT * FROM sys.segments WHERE datasource = 'wikipedia' +``` + +### SEGMENTS table +Segments table provides details on all Druid segments, whether they are published yet or not. + + +|Column|Notes| +|------|-----| +|segment_id|Unique segment identifier| +|datasource|Name of datasource| +|start|Interval start time (in ISO 8601 format)| +|end|Interval end time (in ISO 8601 format)| +|size|Size of segment in bytes| +|version|Version string (generally an ISO8601 timestamp corresponding to when the segment set was first started). Higher version means the more recently created segment. Version comparing is based on string comparison.| +|partition_num|Partition number (an integer, unique within a datasource+interval+version; may not necessarily be contiguous)| +|num_replicas|Number of replicas of this segment currently being served| +|num_rows|Number of rows in current segment, this value could be null if unkown to broker at query time| +|is_published|True if this segment has been published to the metadata store| +|is_available|True if this segment is currently being served by any server| Review comment: I think `server` here is also ambiguous. Does it mean historicals and realtime tasks? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@druid.apache.org For additional commands, e-mail: commits-h...@druid.apache.org