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Author: ksfzhaohui https://my.oschina.net/OutOfMemory/blog/3117737 Recently, there is a demand to analyze an order file, and the description file can reach tens of millions of data, each data is about 20 fields, each field is separated by commas, and it needs to be stored in half an hour as much as possible. thinking 1. Estimate file size Bec ...

Java mentions the persistence layer framework. I believe no one doesn't know the existence of mybatis. Compared with JDBC, it has a more capable (JDBC workload is large), and compared with Hibernate, it has a more flexible (although HQL is convenient, it is too inflexible). Today we are going into her world together. 1, Simple implementation o ...

13 object oriented 13.1 basic concepts Class: A   class is a collection of abstract concepts of events with a series of common characteristics and behaviors. The concept described by class is very similar to that in real life. For example, there are many kinds of creatures, different kinds of food and different kinds of goods. And a clas ...

1. Introducing dependencies <!-- https://mvnrepository.com/artifact/org.apache.mina/mina-core --> <dependency> <groupId>org.apache.mina</groupId> <artifactId>mina-core</artifactId> <version>2.0.7</version> </dependency>   2. Create ...

In the Data Guard environment, there are two types of role switching for databases, Switchover and Failover. According to the name, the former is a normal role switching between the active and standby databases, which will not lose data; the latter is a Failover, which means that the primary database cannot continue to provide services, which m ...

preface By default, Cypress will clear all cookies before each use case starts, ensuring the independence and clean environment of each use case. However, when we want to write multiple test cases in a js file, we want to call login only once, and remember cookies. Later use cases default to login state, so the test is more efficient. There ar ...

Today, a question suddenly comes to mind. Is the DELETE, DROP, TRUNCATE command the same as the binlog in ROW format? It's not the same to remember vaguely, but it's not sure; so let's take a look at the experiment. MySQL:5.6.20MySQL:5.7.22 1. View binlog settings mysql> show variables like 'binlog_format'; +---------------+-------+ | Vari ...

0. Preface In the last article, you basically completed the introductory tutorial for EF Core.Starting with this article, we'll try to explore more ORM frameworks on the.net core platform.So let's start with NHibernate. 1. Introduction to NHibernate NHibernate is the C#version of Hibernate, known as the pillar of ORM in Java (at least once).Hib ...

What is Middleware? Middleware is software that is assembled into application pipelines to process requests and responses. Each component: Choose whether to pass the request to the next component in the pipeline. You can perform work before and after calling the next component in the pipeline. Request delegates are used to build the requ ...

1, shiro internal structure 1. Components contained in shiro shiro mainly includes Authenticator, authorizer, session manager, encryption, remember me and cache manager 2. Introduction to components of shiro Subject: the subject, which can be understood as the user interacting with the application, contains all the information of the us ...