# Hot Table Cache - Principle
__*lease*__
+ Write operations cannot be performed during the lease period

![left](./student-guide/diagram/CachedTablesPrinciple02_aa_001_20220515.png)

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During the lease (lease) time, we can read the table in the cache on the TiDB Server, but write operations are blocked. In other words, the table cannot be modify at this time.