# Main Features Of Tiflash

__*TiFlash*__

+ Unlike TiKV, TiFlash is a columnar storage engine
+ Participate in a TiDB cluster as a Raft Learner
+ Used for OLAP scenario, supports smart selection of engines, and greatly improves query speed


![left](./student-guide/diagram/tidb-cluster-storage-tiflash.png)

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TiFlash provides column oriented store and has a coprocessor layer that is efficiently implement with ClickHouse. In addition, it is very similar to TiKV, relying on the same Multi-Raft system to replicate data in Region.

TiFlash replicates the data in the TiKV cluster in real time with low consumption and non-blocking TiKV writes, while providing consistent read like TiKV, and ensures that the latest data is read. The Region replica in TiFlash corresponds exactly to the TiKV, and is split and merged with the Leader replica in TiKV at the same time.

TiFlash recommends using a different node than TiKV for workload isolation, but you can also choose to deploy on the same node as TiKV without service isolation.

TiFlash accesses the TiDB cluster with the learner role. TiFlash supports table-granular data synchronization. After deployment, no data is synchronized by default, and the synchronization function needs to be explicitly enabled.