# Unique Key in TiKV

![`smart`](ClusteredIndexes04_aa_005_20230922.png)
![`smart`](ClusteredTableWithPrimaryKey_en_001_20231116.png)

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The relational data has been transformed into a `key-value` structure, and the key is unique in the underlying TiKV Map in the TiKV cluster.

In the example shown on the slide, the table prefix is automatically assigned as `t24` and the row prefix is `_r`, resulting in the complete prefix for each key as `t24_r`. The key follows the format of `prefix_PK`, where `PK` indicates the primary key. To summarize, the primary keys in the table are `1, 2, 3, 4, 5, 6`, and the corresponding keys in TiKV are `t24_r1, t24_r2, t24_r3, t24_r4, t24_r5, t24_r6`.