If it is a web application with a large number of visits, the use of foreign keys should be avoided, and the relationship should be maintained by the outer application. The reason is that foreign keys will slow down the data access performance, which will increase the computational burden of the database server. , this part of the computing burden should be handed over to the application server, because the application server has good elastic scalability (load balancing can be done if necessary).
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Do you use foreign keys when designing your database? - Know almost