Annotation Development of mybatis

Commonly used annotations for mybatis: @ Insert: Achieving new additions @ Update: Implementing updates @ Delete: Implementing Delete @ Select: Implementing queries @ Result: Implementing result set encapsulation @ Results: Can be used with @Result to encapsulate multiple result sets @ ResultMap: Enca ...

Posted on Wed, 02 Oct 2019 18:09:53 -0700 by firmolari

Centos7 Builds cloudera-manager Cluster

0. Preparations Close the firewall # All nodes systemctl stop firewalld systemctl disable firewalld No exchange # All nodes sysctl vm.swappiness=0 Disable large pages # All nodes echo never > /sys/kernel/mm/transparent_hugepage/defrag echo never > /sys/kernel/mm/transparent_hugepage/enabled 1,JDK Unload existing Java rpm -qa | grep jav ...

Posted on Wed, 02 Oct 2019 12:36:08 -0700 by slaterino

Database Connection Pool C3p0 and Druid

Database connection pool 1. The database connection pool is a container. There are several connection objects in the container. We can use them directly and return them automatically after using them. It is a factory of physical data sources. DataSource interface 1. java.sql 2. getConnection(); ...

Posted on Wed, 02 Oct 2019 08:41:48 -0700 by tommix

Use of PageHelper in BES-Project

In order to reduce data transmission and realize paging function in the previous section, PageHelper is used in the project. PageInfo is used to return the value. Take the Organization table operation as an example. Controller layer Configuration of pagehelper in application.yml in the controller ...

Posted on Wed, 02 Oct 2019 07:24:57 -0700 by budimir

PostgreSQL DBA( - PG 12 Improving Partition Select

When PG 10 executes queries on partition tables, it checks the constraints of each partition one by one to see if they are needed. If many partitions are partitioned, there will be a significant performance loss during the planning phase. PG 11 improves performance by quickly identifying matched partitions through the partition pruning algorit ...

Posted on Wed, 02 Oct 2019 06:53:25 -0700 by neojordan

Implementation of Paging Technology in jsp

Paging purposes: In order to prevent the server from reading out all the data of the database at one time and improve efficiency. (The database data exists in the form of files, and it is slow to read from the hard disk) Two representations of restricted queries need to be used: limit n: Query n data fr ...

Posted on Wed, 02 Oct 2019 03:28:26 -0700 by tymlls05

Django choices Options and the Use of Rich Text Editors

Project preparation 1. Create a database create database choices_test default charset utf8; 2. Create a Django project named choices_test; 3. Create app01; The project structure is as follows 4. Configure the database; DATABASES = { 'default': { 'ENGINE': 'django.db.backends.mysql', 'NAME': 'choices_test', ...

Posted on Wed, 02 Oct 2019 00:04:58 -0700 by RDKL PerFecT

MySQL Database Foundation: An Example of MySQL Database Creation

Links to the original text: https://blog.51cto.com/9291927/2091340 MySQL Database Foundation (4) - An Example of MySQL Database Creation This article is reproduced from: https://blog.51cto.com/9291927/2091340. I. Creati ...

Posted on Tue, 01 Oct 2019 22:02:19 -0700 by MatthewJ

Design of MyBatis Personnel Management System Database

Sixteen entities User: The corresponding user. Dept: Corresponding departments. Job: Corresponding position. Employee: Corresponding employees. Notice: Corresponding announcements. Document: The corresponding file. II. Inter-entity relations Dept and Employee are one-to-many relationships, ...

Posted on Tue, 01 Oct 2019 19:07:51 -0700 by hrosas

Climb all the skin of heroes in the Heroes Alliance

By analyzing the hero League official page, we enter the database page and analyze the hero's page. There are two types of the same picture, one is the big picture, the other is the small picture similar to the head. Let's grab the big picture here. Get several image links and analyze https://game.gtimg ...

Posted on Tue, 01 Oct 2019 18:38:29 -0700 by plinares