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ClickHouse/docs/en/operations/system-tables/table_engines.md
Ivan Blinkov 7170f3c534
[docs] split aggregate function and system table references (#11742) 
* prefer relative links from root

* wip

* split aggregate function reference

* split system tables
2020-06-18 11:24:31 +03:00

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system.table_engines

Contains description of table engines supported by server and their feature support information.

This table contains the following columns (the column type is shown in brackets):

  • name (String) — The name of table engine.
  • supports_settings (UInt8) — Flag that indicates if table engine supports SETTINGS clause.
  • supports_skipping_indices (UInt8) — Flag that indicates if table engine supports skipping indices.
  • supports_ttl (UInt8) — Flag that indicates if table engine supports TTL.
  • supports_sort_order (UInt8) — Flag that indicates if table engine supports clauses PARTITION_BY, PRIMARY_KEY, ORDER_BY and SAMPLE_BY.
  • supports_replication (UInt8) — Flag that indicates if table engine supports data replication.
  • supports_duduplication (UInt8) — Flag that indicates if table engine supports data deduplication.

Example:

SELECT *
FROM system.table_engines
WHERE name in ('Kafka', 'MergeTree', 'ReplicatedCollapsingMergeTree')

┌─name──────────────────────────┬─supports_settings─┬─supports_skipping_indices─┬─supports_sort_order─┬─supports_ttl─┬─supports_replication─┬─supports_deduplication─┐
│ Kafka                         │                 1 │                         0 │                   0 │            0 │                    0 │                      0 │
│ MergeTree                     │                 1 │                         1 │                   1 │            1 │                    0 │                      0 │
│ ReplicatedCollapsingMergeTree │                 1 │                         1 │                   1 │            1 │                    1 │                      1 │
└───────────────────────────────┴───────────────────┴───────────────────────────┴─────────────────────┴──────────────┴──────────────────────┴────────────────────────┘

See also