Runtime Information

The INFORMATION_SCHEMA database provides access to system metadata, such as the name of a database or table, the data type of a column, etc.

• Find the topology information of the cluster though CLUSTER_INFO table.
• Find the table regions distribution though PARTITIONS and REGION_PEERS tables.

For example, find all the region id of a table:

SELECT greptime_partition_id FROM PARTITIONS WHERE table_name = 'monitor'

Find the distribution of all regions in a table:

SELECT b.peer_id as datanode_id,
       a.greptime_partition_id as region_id
FROM information_schema.partitions a LEFT JOIN information_schema.region_peers b
ON a.greptime_partition_id = b.region_id
WHERE a.table_name='monitor'
ORDER BY datanode_id ASC

For more information about the INFORMATION_SCHEMA database, Please read the reference.