What is html2canvas ?
The script allows you to take “screenshots” of webpages or parts of it, directly on the users browser. The screenshot is based on the DOM and as such may not be 100% accurate to the real representation as it does not mak…
1、查询重复数据
SELECT a.*
FROM table_a a
INNER JOIN (SELECT id_customerFROM table_aGROUP BY id_customerHAVING COUNT(*) > 1
) b ON a.id_customer b.id_customer;说明:
子查询(子选择b)选择所有id_customer并计算每个id_custo…
spring概述
spring 是什么
Spring 框架是由于软件开发的复杂性而创建的。Spring使用的是基本的JavaBean 来完成以前只可能由 EJB 完成的事情。然而,Spring的用途不仅仅限于服务器端的开发。从简单性、可测试性和松耦合性角度而言,绝大部分Java应用都可…