ClickHouse/docs/en/operations/system-tables/table_engines.md

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2022-04-03 23:05:35 +00:00
# system.table_engines {#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](../../engines/table-engines/mergetree-family/mergetree.md#table_engine-mergetree-data_skipping-indexes).
- `supports_ttl` (UInt8) — Flag that indicates if table engine supports [TTL](../../engines/table-engines/mergetree-family/mergetree.md#table_engine-mergetree-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](../../engines/table-engines/mergetree-family/replication.md).
- `supports_duduplication` (UInt8) — Flag that indicates if table engine supports data deduplication.
- `supports_parallel_insert` (UInt8) — Flag that indicates if table engine supports parallel insert (see [`max_insert_threads`](../../operations/settings/settings.md#settings-max-insert-threads) setting).
Example:
``` sql
SELECT *
FROM system.table_engines
WHERE name in ('Kafka', 'MergeTree', 'ReplicatedCollapsingMergeTree')
```
``` text
┌─name──────────────────────────┬─supports_settings─┬─supports_skipping_indices─┬─supports_sort_order─┬─supports_ttl─┬─supports_replication─┬─supports_deduplication─┬─supports_parallel_insert─┐
│ MergeTree │ 1 │ 1 │ 1 │ 1 │ 0 │ 0 │ 1 │
│ Kafka │ 1 │ 0 │ 0 │ 0 │ 0 │ 0 │ 0 │
│ ReplicatedCollapsingMergeTree │ 1 │ 1 │ 1 │ 1 │ 1 │ 1 │ 1 │
└───────────────────────────────┴───────────────────┴───────────────────────────┴─────────────────────┴──────────────┴──────────────────────┴────────────────────────┴──────────────────────────┘
```
**See also**
- MergeTree family [query clauses](../../engines/table-engines/mergetree-family/mergetree.md#mergetree-query-clauses)
- Kafka [settings](../../engines/table-engines/integrations/kafka.md#table_engine-kafka-creating-a-table)
- Join [settings](../../engines/table-engines/special/join.md#join-limitations-and-settings)
[Original article](https://clickhouse.com/docs/en/operations/system-tables/table_engines) <!--hide-->