The core logic of a database application is performed through SQL statements, whether issued directly through an interpreter or submitted behind the scenes through an API. 数据库应用程序的核心逻辑是通过SQL语句执行的，无论是通过解释器直接发出的，还是通过API在后台提交的。The tuning guidelines in this section help to speed up all kinds of MySQL applications. 本节中的调优指南有助于提高各种MySQL应用程序的速度。The guidelines cover SQL operations that read and write data, the behind-the-scenes overhead for SQL operations in general, and operations used in specific scenarios such as database monitoring.这些指导方针包括读写数据的SQL操作、一般SQL操作的幕后开销，以及在特定场景（如数据库监视）中使用的操作。