# Non-Distributed RDBMS Scale-Out Attempt B: Database Sharding

__*Traditional Database Sharding Weakness*__

![left](./student-guide/diagram/horizontal-sharding.drawio.png)

+ Take horizontal sharding as an example

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From the above graph, it may not be very impactful, and it is not a case in the real world to cut a workload to more than 40 libraries. Moreover, the convenience of SQL statement disappears under the barriers of the database, because these sharding are housed in different databases, not real cluster, not cluster can't really share schema information, applications need to take more responsibility, and it's a disaster for operation and management.