# Hot Table Cache- Principle
+ The data has been updated, and the lease continues to open

![left](./student-guide/diagram/CachedTablesPrinciple04_aa_001_20220515.png)

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When the data is updated, the lease (lease) starts to be re-timed, and the write operation continues to be blocked. At this time, the data is reloaded into the TiDB Server cache, and the read operation can retrieve the data from the TiDB Server cache.