ARTS01

What is ARTS ?

Algorithm每周至少做一个leetcode算法题

Review阅读并点评至少一篇英文技术文章

Tip学习至少一个技术技巧

Share分享一篇有观点和思考的技术文章

Algorithm

Two Sum Sulution

https://leetcode.com/problems/two-sum/description/

Review

Understanding MySQL Queries with Explain

https://www.exoscale.com/syslog/explaining-mysql-queries/

columns:

id (query id)

select_type (type of statement)

table (table referenced)

type (join type)

possible_keys (which keys could have been used)

key (key that was used)

key_len (length of used key)

ref (columns compared to index)

rows (amount of rows searched)

Extra (additional information)

The main points for long-term performance summarized:

create a sustainable data model that suits your company’s needs

choose the right form of database

use a software architecture that matches your product

go through regular iterations of looking at the structure of your queries and use on the more convoluted ones, optimize usage for your chosen database(s), also with regard to database updates and how they could affect you

choose the instances that best suit your application and database needs in accordance with performance and bandwidth

Tip

多模块项目，扫描不到另一个module的service，无法使用注入。

原因分析：SpringBoot默认在Application启动类的同级package开始往下扫描，另一个module的service包名在启动类包的上一级，所以扫描不到。

解决办法：在springboot启动类上增加指定扫描的package，或者调整SpringBootApplication启动类的位置。

原因分析：在idea下，maven默认到目录下拷贝xml文件，而我把mapper.xml放在了的package下，编译后target下找不到mapper.xml文件，故抛出该异常

解决方法：在pom.xml文件的build标签下增加resources。

Share

Adapter Design Pattern in Java

https://www.journaldev.com/1487/adapter-design-pattern-java

架构师的自我修养