系统。表_engines
包含服务器支持的表引擎的描述及其功能支持信息。
此表包含以下列(列类型显示在括号中):
- name(String) — The name of table engine.
- supports_settings(UInt8) — Flag that indicates if table engine supports- SETTINGS条款
- supports_skipping_indices(UInt8) — Flag that indicates if table engine supports 跳过索引.
- 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和- SAMPLE_BY.
- supports_replication(UInt8) — Flag that indicates if table engine supports 数据复制.
- supports_duduplication(UInt8) — Flag that indicates if table engine supports data deduplication.
示例:
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 │
└───────────────────────────────┴───────────────────┴───────────────────────────┴─────────────────────┴──────────────┴──────────────────────┴────────────────────────┘
另请参阅