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Integrate Mybatis <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.2</version> </dependency> Steps: 1) . configure data source related properties (see Druid in the previous section) 2) . creating tables for data ...

I often use SQL in my work, which has annoying subtle differences and limitations, but after all, it is the cornerstone of the data industry.Therefore, SQL is indispensable to every data worker.Being proficient in SQL means a lot. SQL is good, but how can you just be satisfied with "good"?Why not proceed further with SQL? Statements c ...

There are too many if else in the coding. On the one hand, the original design didn't pay attention to it; on the other hand, it may be because of the changing requirements. But a lot of if else in the code knows that this situation is not good, so let's talk about how to optimize this situation if(Condition 1){ .... }else if(Condition 2){ ...

Hello, I'm miniluo. For positions requiring distributed experience, interviewers always like to ask questions about distributed locks. Recently, I have the honor to participate in the company's interview, and I often ask about the knowledge of distributed locks. Most of the candidates' answers are more limited to using, and they have not though ...

Thank you for your reference- http://bjbsair.com/2020-04-01/tech-info/18398.html This article will record the CSS fragments that we usually use. Using these CSS can help us solve many practical project problems. It's suggested to like the collection of wall cracks for later reference Attach note link, read more high-quality articles in the pas ...

Java's dynamic Proxy mainly refers to the Proxy class under the java.lang.reflect package. The InvocationHandler interface under the same package will be used in the use process. 1. The proxy class provides a static method object newproxyinstance (classloader loader, class <? > [] interfaces, invocationhandler h) to generate proxy objects ...

tcp programming -- client obtains server input and output stream Train of thought: Step 1: instantiate a ServerSocket object (server socket) to wait for requests on the network (that is, the socket waiting to connect) Step 2: call the accept() method to return a socket object connected to the client socket object Step 3: the output stream obtai ...

Regular expression 1, Introduction & overview Why regular expressions? Help us simplify string operation (judgment, replacement, cutting ). Regular expressions: expressions with correct rules   Effect: Simplify string operation (judgment, replacement, cutting ).   Pseudo code: Determine whether the current string is a QQ n ...

Scala Actor concurrent programming WordCount Demand: Write a stand-alone WordCount with actor concurrent programming, take multiple files as input, summarize multiple tasks after calculation, and get the final result. General steps: 1. Continuously receive messages through loop +react 2. Using case class sample cla ...

Objectives: Send the supplier extension list separated from the last note to the email address of different suppliers in the form of attachment. The code test sends an email every second   The code is as follows     #!/usr/bin/env python # coding: utf-8 # In[49]: import smtplib from email import encoders from email.header imp ...