1.从Java EE 5规范开始,Servlet中增加了两个影响Servlet生命周期的注解(Annotion):@PostConstruct和@PreDestroy.这两个注解被用来修饰一个非静态的void()方法 .写法有如下两种方式: @PostConstruct Public void someMethod() {} 或者 public @PostConstruct void someMethod(){} 被@PostConstruct修饰的方法会在服务器加载Servle的时候运行,并且…
1.单表的:update user set name = (select name from user where id in (select id from user where name='小苏')): update goods set name = REPLACE(name ,' ','') ; //去空格 update goods set name = replace(name,'香蕉','苹果') ; //香蕉换苹果 u…