system_history.access_history

This table provides detailed logging of objects accessed and modified by each query, including tables, columns, and stages, as part of the query metadata. It provides structured information about DDL and DML operations to enhance auditing.

Fields

Field	Type	Description
query_id	VARCHAR	The ID of the query.
query_start	TIMESTAMP	The start time of the query.
user_name	VARCHAR	The name of the user who executed the query.
base_objects_accessed	VARIANT	The objects accessed by the query.
direct_objects_accessed	VARIANT	Reserved for future use; currently not in use.
objects_modified	VARIANT	The objects modified by the query.
object_modified_by_ddl	VARIANT	The objects modified by the DDL (e.g CREATE TABLE, ALTER TABLE).

The fields base_objects_accessed, objects_modified, and object_modified_by_ddl are all arrays of JSON objects. Each object may include the following fields:

• object_domain: The type of object, one of [Database, Table, Stage].
• object_name: The name of the object. For stages, this is the stage name.
• columns: Column information, present only when object_domain is Table.
• stage_type: The type of stage, present only when object_domain is Stage.
• operation_type: The DDL operation type, one of [Create, Alter, Drop, Undrop], present only in the object_modified_by_ddl field.
• properties: Detailed information about the DDL operation, present only in the object_modified_by_ddl field.

Examples

CREATE TABLE t (a INT, b string);

Will be recorded as:

               query_id: c2c1c7be-cee4-4868-a28e-8862b122c365
            query_start: 2025-06-12 03:31:19.042128
              user_name: root
  base_objects_accessed: []
direct_objects_accessed: []
       objects_modified: []
 object_modified_by_ddl: [{"object_domain":"Table","object_name":"default.default.t","operation_type":"Create","properties":{"columns":[{"column_name":"a","sub_operation_type":"Add"},{"column_name":"b","sub_operation_type":"Add"}],"create_options":{"compression":"zstd","database_id":"1","storage_format":"parquet"}}}]

CREATE TABLE is a DDL operation, so it will be recorded in the object_modified_by_ddl field.

INSERT INTO t VALUES (1, 'book');

Will be recorded as:

               query_id: e92ebc00-a07e-4138-92a9-ea17a06f0165
            query_start: 2025-06-12 03:31:29.849848
              user_name: root
  base_objects_accessed: []
direct_objects_accessed: []
       objects_modified: [{"columns":[{"column_name":"a"},{"column_name":"b"}],"object_domain":"Table","object_name":"default.default.t"}]
 object_modified_by_ddl: []

INSERT INTO is a DML operation, so it will be recorded in the objects_modified field.

COPY INTO @s FROM t;

               query_id: 7fd74374-c04a-4989-a6f7-bfe8cc27e511
            query_start: 2025-06-12 03:32:25.682248
              user_name: root
  base_objects_accessed: [{"columns":[{"column_name":"a"},{"column_name":"b"}],"object_domain":"Table","object_name":"default.default.t"}]
direct_objects_accessed: []
       objects_modified: [{"object_domain":"Stage","object_name":"s","stage_type":"Internal"}]
 object_modified_by_ddl: []

The COPY INTO operation from table t to internal stage s involves both read and write actions. After executing this query, the source table will be recorded in the base_objects_accessed field, and the target stage will be recorded in the objects_modified field.