# TiDB's HTAP Architecture

![`smart`](TiDBHTAP_aa_002_20220512.png)

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The changes in the figure are that TiFlash is added to the storage cluster, and the TiFlash nodes join the Multi-Raft Group in the Raft Learner mode, and the data is synchronized in a quasi-real-time synchronization mode. After the data is synchronized to TiFlash, it will be converted from row format to column format.

TiFlash related implementation mainly includes the following principles:
1. Columnar storage.
2. Ensure the real-time synchronization of TiKV.
3. Data consistency.
4. Engine smart selection between TiDB and TiKV for query.

In addition to column storage, TiDB also supports MPP computing architecture on TiFlash, which plays a very obvious role in accelerating aggregation and join.