system.query_log

Introduced or updated: v1.2.957

A read-only in-memory table stores all the query logs. For the specific fields available in the query logs, refer to the Examples section.

Credential Masking

Query history masks values in recognized credential-bearing SQL syntax. Examples include user passwords, connection credentials, remote UDF headers and URL credentials, webhook options, and secret-named settings. Valid query and DML expressions remain visible. A predicate such as WHERE token = 'abc' is user data, not a credential option, so its literal is not automatically hidden.

For SQL that cannot be parsed, history masking hides values while preserving statement structure for diagnosis. Logged error copies are scrubbed using the hidden values recorded for the statement. Errors returned to the submitting client are not changed by this scrubbing.

Logs can still contain sensitive data

Masking is not a general data-redaction policy. Pre-planning request logs use a different masking path. Malformed SQL, unrecognized credential option names, and some procedure arguments or task scripts can still expose credentials there. Transformed secret values and short unquoted values can also escape error scrubbing. Restrict access to query history and server logs. Do not put secrets in ordinary query literals.

Setting a Session Tag

You can optionally assign a tag to your session, making it easier to filter logs in the log table based on the assigned session tag. For example, the following assigns the tag eric to the current session:

set session query_tag='eric';

We can then run a query and retrieve the log from the log table using the assigned tag:

show users;

select query_tag, query_text from system.query_log where query_tag='eric' limit 1;

In the returned result, you can find the record for the query, tagged as 'eric':

-[ RECORD 1 ]-----------------------------------
               query_tag: eric
              query_text: SHOW USERS

Examples

The system.query_log table stores detailed logs of executed queries. Here's an example of what the log entry looks like:

SELECT * FROM system.query_log;

...
-[ RECORD 10 ]-----------------------------------
                log_type: 2
           log_type_name: Finish
            handler_type: HTTPQuery
               tenant_id: default
              cluster_id: default
                 node_id: bwElPLZxWt0F8LOFAqsIL2
                sql_user: root
          sql_user_quota: UserQuota<cpu:0,mem:0,store:0>
     sql_user_privileges: ROLES: ["account_admin"]
                query_id: 1957f343-564e-471f-b036-a10ff853357e
              query_kind: Other
              query_text: SHOW USERS
              query_hash: 63c65a28ae257d780e93a8a627190775
query_parameterized_hash: 63c65a28ae257d780e93a8a627190775
              event_date: 2025-04-27
              event_time: 2025-04-27 16:59:31.681036
        query_start_time: 2025-04-27 16:59:31.671825
       query_duration_ms: 9
query_queued_duration_ms: 0
        current_database: default
               databases:
                  tables:
                 columns:
             projections:
            written_rows: 0
           written_bytes: 0
       join_spilled_rows: 0
      join_spilled_bytes: 0
        agg_spilled_rows: 0
       agg_spilled_bytes: 0
   group_by_spilled_rows: 0
  group_by_spilled_bytes: 0
        written_io_bytes: 0
written_io_bytes_cost_ms: 0
               scan_rows: 1
              scan_bytes: 164
           scan_io_bytes: 0
   scan_io_bytes_cost_ms: 0
         scan_partitions: 0
        total_partitions: 0
             result_rows: 1
            result_bytes: 146
               cpu_usage: 8
            memory_usage: 0
  bytes_from_remote_disk: 0
   bytes_from_local_disk: 0
       bytes_from_memory: 0
             client_info:
          client_address: 192.168.65.1
              user_agent: bendsql/0.24.1-f1f7de0
          exception_code: 0
          exception_text:
             stack_trace:
          server_version: v1.2.731-nightly-eb671da5e5(rust-1.88.0-nightly-2025-04-27T06:06:12.942159732Z)
               query_tag: eric
        session_settings: acquire_lock_timeout=30, aggregate_spilling_memory_ratio=60, auto_compaction_imperfect_blocks_threshold=25, auto_compaction_segments_limit=3, collation=utf8, compact_max_block_selection=10000, copy_dedup_full_path_by_default=0, cost_factor_aggregate_per_row=5, cost_factor_hash_table_per_row=10, cost_factor_network_per_row=50, create_query_flight_client_with_current_rt=1, data_retention_time_in_days=1, ddl_column_type_nullable=1, default_order_by_null=nulls_last, disable_join_reorder=0, disable_variant_check=0, dynamic_sample_time_budget_ms=0, efficiently_memory_group_by=0, enable_aggregating_index_scan=1, enable_analyze_histogram=0, enable_auto_fix_missing_bloom_index=0, enable_auto_vacuum=0, enable_block_stream_write=0, enable_bloom_runtime_filter=1, enable_cbo=1, enable_clickhouse_handler=0, enable_compact_after_multi_table_insert=0, enable_compact_after_write=1, enable_dio=1, enable_distributed_compact=0, enable_distributed_copy_into=1, enable_distributed_merge_into=1, enable_distributed_pruning=1, enable_distributed_recluster=0, enable_distributed_replace_into=0, enable_dphyp=1, enable_dst_hour_fix=0, enable_expand_roles=1, enable_experimental_aggregate_hashtable=1, enable_experimental_merge_into=1, enable_experimental_procedure=0, enable_experimental_queries_executor=0, enable_geo_create_table=0, enable_hive_parquet_predict_pushdown=1, enable_last_snapshot_location_hint=1, enable_loser_tree_merge_sort=1, enable_materialized_cte=1, enable_merge_into_row_fetch=1, enable_new_copy_for_text_formats=1, enable_optimizer_trace=0, enable_parallel_multi_merge_sort=1, enable_parquet_page_index=1, enable_parquet_prewhere=0, enable_parquet_rowgroup_pruning=1, enable_planner_cache=1, enable_prune_cache=1, enable_prune_pipeline=1, enable_query_result_cache=0, enable_refresh_aggregating_index_after_write=1, enable_replace_into_partitioning=1, enable_strict_datetime_parser=1, enable_table_lock=1, enforce_broadcast_join=0, enforce_shuffle_join=0, error_on_nondeterministic_update=1, external_server_connect_timeout_secs=10, external_server_request_batch_rows=65536, external_server_request_max_threads=256, external_server_request_retry_times=8, external_server_request_timeout_secs=180, flight_client_timeout=60, flight_connection_max_retry_times=0, flight_connection_retry_interval=1, force_aggregate_data_spill=0, force_join_data_spill=0, force_sort_data_spill=0, force_window_data_spill=0, format_null_as_str=1, geometry_output_format=GeoJSON, group_by_shuffle_mode=before_merge, group_by_two_level_threshold=20000, hide_options_in_show_create_table=1, hilbert_clustering_min_bytes=107374182400, hilbert_num_range_ids=1000, hilbert_sample_size_per_block=1000, hive_parquet_chunk_size=16384, http_handler_result_timeout_secs=60, idle_transaction_timeout_secs=14400, inlist_to_join_threshold=1024, input_read_buffer_size=4194304, join_spilling_buffer_threshold_per_proc_mb=512, join_spilling_memory_ratio=60, join_spilling_partition_bits=4, lazy_read_threshold=1000, load_file_metadata_expire_hours=24, max_block_size=65536, max_cte_recursive_depth=1000, max_execute_time_in_seconds=0, max_inlist_to_or=3, max_memory_usage=6574653440, max_push_down_limit=10000, max_query_memory_usage=0, max_result_rows=0, max_set_operator_count=18446744073709551615, max_spill_io_requests=48, max_storage_io_requests=48, max_threads=8, max_vacuum_temp_files_after_query=18446744073709551615, network_policy=, numeric_cast_option=rounding, optimizer_skip_list=, parquet_fast_read_bytes=16777216, parquet_max_block_size=8192, parse_datetime_ignore_remainder=1, persist_materialized_cte=0, prefer_broadcast_join=1, purge_duplicated_files_in_copy=0, query_flight_compression=LZ4, query_out_of_memory_behavior=throw, query_result_cache_allow_inconsistent=0, query_result_cache_max_bytes=1048576, query_result_cache_min_execute_secs=1, query_result_cache_ttl_secs=300, query_tag=eric, quoted_ident_case_sensitive=1, random_function_seed=0, recluster_block_size=1972396032, recluster_timeout_secs=43200, replace_into_bloom_pruning_max_column_number=4, replace_into_shuffle_strategy=0, sandbox_tenant=, script_max_steps=10000, short_sql_max_length=128, sort_spilling_batch_bytes=8388608, sort_spilling_memory_ratio=60, spilling_file_format=parquet, spilling_to_disk_vacuum_unknown_temp_dirs_limit=18446744073709551615, sql_dialect=PostgreSQL, statement_queue_ttl_in_seconds=15, statement_queued_timeout_in_seconds=0, storage_fetch_part_num=2, storage_io_max_page_bytes_for_read=524288, storage_io_min_bytes_for_seek=48, storage_read_buffer_size=1048576, stream_consume_batch_size_hint=0, table_lock_expire_secs=30, timezone=UTC, unquoted_ident_case_sensitive=0, use_parquet2=0, use_vacuum2_to_purge_transient_table_data=0, warehouse=, window_num_partitions=256, window_partition_sort_block_size=65536, window_partition_spilling_memory_ratio=60, window_partition_spilling_to_disk_bytes_limit=0, window_spill_unit_size_mb=256, scope: SESSION
                   extra:
             has_profile: true
       peek_memory_usage: {"bwElPLZxWt0F8LOFAqsIL2":576850}