system.merge_tree_settings

Contains information about settings for MergeTree tables.

Columns:

  • name (String) — Setting name.
  • value (String) — Setting value.
  • description (String) — Setting description.
  • type (String) — Setting type (implementation specific string value).
  • changed (UInt8) — Whether the setting was explicitly defined in the config or explicitly changed.

Example

  1. :) SELECT * FROM system.merge_tree_settings LIMIT 4 FORMAT Vertical;
  1. Row 1:
  2. ──────
  3. name:        index_granularity
  4. value:       8192
  5. changed:     0
  6. description: How many rows correspond to one primary key value.
  7. type:        SettingUInt64
  9. Row 2:
  10. ──────
  11. name:        min_bytes_for_wide_part
  12. value:       0
  13. changed:     0
  14. description: Minimal uncompressed size in bytes to create part in wide format instead of compact
  15. type:        SettingUInt64
  17. Row 3:
  18. ──────
  19. name:        min_rows_for_wide_part
  20. value:       0
  21. changed:     0
  22. description: Minimal number of rows to create part in wide format instead of compact
  23. type:        SettingUInt64
  25. Row 4:
  26. ──────
  27. name:        merge_max_block_size
  28. value:       8192
  29. changed:     0
  30. description: How many rows in blocks should be formed for merge operations.
  31. type:        SettingUInt64
  33. 4 rows in set. Elapsed: 0.001 sec.

Original article