# Relational Data and KV Transformation: Region and TiKV

![`smart`](Table2KV07_aa_002_20220509.png)

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By default, one Region in TiDB is 96 MB maximum, that is, when 96 MB is reached, it will be split into two Regions. This avoids the problem that the Region is too large.

After that, these Regions will be distributed to each storage node, which is what we call TiKV nodes, so that our data tables are automatically sharded and distributed.

The distribution information of the Region is stored in the PD nodes, and each time the SQL statement is executed, the location of the Region where the data is to be found is read from the PD node. TiDB server has a `TiKV Client` module to cache the Region information for performance reason, it will be discussed more in the unit "Placement Driver Server".