ClickHouse/docs/en/system_tables/system.settings.rst

system.settings
---------------

Contains information about settings that are currently in use (i.e. used for executing the query you are using to read from the system.settings table).

Columns:
::
  name String   - Setting name.
  value String  - Setting value.
  changed UInt8 - Whether the setting was explicitly defined in the config or explicitly changed.

Example:

.. code-block:: sql

  SELECT *
  FROM system.settings
  WHERE changed
  
  ┌─name───────────────────┬─value───────┬─changed─┐
  │ max_threads            │ 8           │       1 │
  │ use_uncompressed_cache │ 0           │       1 │
  │ load_balancing         │ random      │       1 │
  │ max_memory_usage       │ 10000000000 │       1 │
  └────────────────────────┴─────────────┴─────────┘