# After Top Sql

![left](./student-guide/diagram/TopSQLAfter_en_001_20220515.png)

------------------------------------------------------------
The Top SQL feature of TiDB Dashboard allows you to visually monitor and explore the CPU overhead of each SQL statement in the database during execution, so as to optimize and address database performance issues. Top SQL continuously collects data such as the real-time CPU load per second of each TiDB and TiKV instance (counted separately by SQL type) and stores it for up to 30 days. You can use the charts and tables displayed by Top SQL to quickly analyze which SQL statements the high CPU load of a TiDB or TiKV instance comes from in a certain period of time.

Top SQL has the following features:

- Visually display the 5 types of SQL statements overhead the most CPU through charts and tables.

- Display detailed execution information such as number of request per second, average delay, query schedule, etc.

- Support for counting all SQL statements that are being executed but have not yet been executed.

- Supports checking the status of TiDB and TiKV instances specified in the cluster.