That's enough for rodert to teach you MyBatis-Actual Warfare

[toc] Article content picture upload failed, welcome to read, eBook in white. Preface Statement: Refer to the source Internet, any disputes can be left a message.Standing on the shoulders of the forefathers, we can see farther.This tutorial is all hands-on, dedicated to the most practical tutorials, does not require any rewards, and only wishe ...

Posted by bambambanana on Sat, 13 Jun 2020 10:41:23 -0700

[Abp vNext microservice practice] - Business Development

In the previous several articles, we introduced abp vNext microservice framework, development environment construction and access to the front-end framework of vue element admin respectively. After the basic functions of user role management are implemented in vue element admin, we can start business development. This article will introduce how ...

Posted by lou28 on Fri, 12 Jun 2020 03:15:14 -0700

Ganyibo ~ write a simple version of Mybatis, and take you to have a deep understanding of its charm!

Zero. Preparations <dependencies> <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.20</version> </dependency> <!-- https://mvnre ...

Posted by coco777 on Thu, 11 Jun 2020 20:04:13 -0700

MySQL Summary Table Join Query (Internal and External Joins) - Detailed

Table Join Query 1. What is a multi-table query Preparing data # Create Department Table create table dept( id int primary key auto_increment, name varchar(20) ) insert into dept (name) values ('Development Department'),('Marketing Department'),('Finance Department'); # Create employee table create table emp ( id int primary key auto_in ...

Posted by 8ta8ta on Thu, 11 Jun 2020 18:00:37 -0700

mybatis Source Parsing Interpretation Level 1 and Level 2 Cache

mybatis cache Mybatis caches have a first-level cache and a second-level cache. Why do mybatis use two caching mechanisms?Let's move on to today's topic with questions. mybatis Level 1 Cache When the mybatis cache executes the same SQL and the same parameters, it does not make repeated calls to the ...

Posted by dudeddy on Wed, 10 Jun 2020 09:29:36 -0700

Analysis on the basic positioning of Mysql performance bottleneck

In the process of performance test, we often encounter the performance bottleneck of Mysql. For the database, the so-called performance bottleneck is nothing more than slow SQL, high CPU, high IO, and high memory. The first three examples are used for performance analysis. Finally, the high memory is ...

Posted by jvanv8 on Tue, 09 Jun 2020 19:30:00 -0700

Django - Lifecycle of Requests & Templates & Routing

Lifecycle requested in Django 1. Overview First, we know that all data transferred in HTTP requests and server responses is strings. In Django, when we visit a url, we enter the corresponding html page through route matching. Django's request life cycle is what happens behind the scenes when a user enters a url into the browser and the user see ...

Posted by strangebeer on Tue, 09 Jun 2020 19:18:49 -0700

Using ibis, impyla, pyhive and pyspark to connect to Hive and Impala of Kerberos security authentication in Python

There are many ways to connect hive and impala in python, including pyhive,impyla,pyspark,ibis, etc. in this article, we will introduce how to use these packages to connect hive or impala, and how to pass kerberos authentication. Kerberos If the cluster does not enable kerberos authentication, the ...

Posted by RunningUtes on Mon, 08 Jun 2020 23:22:07 -0700

spark structured streams, creating streaming DataFrame s and streaming Datasets

Create Streaming DataFrame and Streaming Datasets Streaming DataFrames are available through SparkSession.readStream() The returned DataStreamReader interface (Scala / Java / Python document) is created. Input Sources Common built-in Sources File source: Reads files from a specified directory as st ...

Posted by IwnfuM on Sun, 07 Jun 2020 18:13:27 -0700

Database security and transaction operation

Database security and transaction operation Article catalog Database security and transaction operation 1, Purpose and requirements 2, Experiment content 1. Design the security mechanism so that the user Wang Ming can only find the staff of the financial department 2 design a role_Emp ", this ...

Posted by bbbaldie on Sun, 07 Jun 2020 03:19:54 -0700