system_history.log_history

Stores raw log entries ingested from various nodes. This table acts as the primary source for subsequent log transformations.

All the other log tables are derived from this table, the difference is that other log tables will do some transformations to make the data more structured.

Fields

Field	Type	Description
timestamp	TIMESTAMP	The timestamp when the log entry was recorded
path	VARCHAR	Source file path and line number of the log
target	VARCHAR	Target module or component of the log
log_level	VARCHAR	Log level (e.g., INFO, ERROR)
cluster_id	VARCHAR	Identifier of the cluster
node_id	VARCHAR	Identifier of the node
warehouse_id	VARCHAR	Identifier of the warehouse
query_id	VARCHAR	Query ID associated with the log
message	VARCHAR	Log message content
fields	VARIANT	Additional fields (as a JSON object)
batch_number	BIGINT	Internal use, no special meaning

Note: The message field stores plain text logs, while the fields field stores logs in JSON format.

For example, the fields field of a log entry might look like:

fields: {"node_id":"8R5ZMF8q0HHE6x9H7U1gr4","query_id":"72d2319a-b6d6-4b1d-8694-670137a40d87","session_id":"189fd3e2-e6ac-48c3-97ef-73094c141312","sql":"select * from system_history.log_history"}

the message field of another log entry might appear as follows:

message: [HTTP-QUERY] Preparing to plan SQL query

Examples

SELECT * FROM system_history.log_history LIMIT 1;

*************************** 1. row ***************************
   timestamp: 2025-06-03 01:29:49.335455
        path: databend_common_meta_client::channel_manager: channel_manager.rs:86
      target: databend_common_meta_client::channel_manager
   log_level: INFO
  cluster_id: test_cluster
     node_id: CkdmtwYXLRMhJIvVzl6i11
warehouse_id: NULL
    query_id: NULL
     message: MetaChannelManager done building RealClient to 127.0.0.1:9191, start handshake
      fields: {}
batch_number: 41