Database System SSD7 Experiment 4 Trigger and Cursor

Experiment 4 Triggers and Cursors I. Experimental Purpose _Familiar with the method of database integrity control by SQL statement, understand the concept, definition method and trigger condition of trigger. Understand how cursors are defined, opened, used, closed and released. II. EXPERIMENTAL CO ...

Posted on Sun, 04 Aug 2019 05:08:35 -0700 by jkatcher

SQL Monitoring, the Key Technology of Java Call Chain Tracking

I. General Thought of SQL Monitoring In Java, SQL monitoring is generally implemented through proxy mode, as follows: On the right is the JDBC interface class. On the left is the proxy class, which needs to implement the JDBC interface and hold object instances of the interface class. The database connection factory used to get the JDBC inte ...

Posted on Sun, 04 Aug 2019 04:13:50 -0700 by Simply Me

[Start class javaEE 190802 per day] Basic overview of mybatis and first program

Introduction to mybatis What is mybatis MyBatis is an excellent persistence layer framework and is a semi-automated ORM framework It encapsulates the process of using JDBC to manipulate the database so that developers only need to focus on the SQL itself rather than on the complex process code of jdbc, such as registering drivers, creating con ...

Posted on Fri, 02 Aug 2019 17:50:38 -0700 by cody44

What is the ghost of MySQL binlog failing to recover data based on time?

Problem phenomena A customer feedback, when using binlog to do point-based recovery, often fails to correctly restore data (the probability is about 5%~10%). The database environment provides MySQL 5.7.27 version of cascade replication topology (A->B->C), main library A provides write ...

Posted on Thu, 01 Aug 2019 20:37:55 -0700 by dougp23

EMQ X rule engine series stores messages to MySQL database

Scenario introduction This scenario requires storing qualified messages under EMQ X specified topics into the MySQL database. In order to facilitate subsequent analysis and retrieval, message content needs to be split and stored. In this scenario, the device side reports the following information: Subject: cmd/state/:id, in which ID represents ...

Posted on Wed, 31 Jul 2019 04:50:41 -0700 by Drace

Learning Notes - User Login Case

Demand: Write login.html login page Using Druid database connection pool technology to manipulate user tables in mysql database Encapsulation of JDBC using JdbcTemplate Technology Log in successfully jumped to Success Servlet display: Log in successfully! User name, welcome to you Logon Failure Jump to ...

Posted on Wed, 31 Jul 2019 01:43:03 -0700 by big_al

MyBatis Learning Records

Project Download The project contains code, required jar packages and sql files I. Introduction to MyBatis MyBatis, like Hibernate, is an orm persistence framework. Native jdbc operations have a lot of repetitive code (such as registration driver, connection creation, statement creation, result set ...

Posted on Tue, 30 Jul 2019 06:58:52 -0700 by dimxasnewfrozen

mysql log system inventory

MySql log files include error log, slow query log, transaction log, binary log, etc. Mysql logs can be configured by command 1 show global variables like '%log%'; The results of implementation are as follows "back_log" "80" "binlog_cache_size" "32768" "binlog_checksum" "CRC32" "binlog_direct_non_transactional_updates" ...

Posted on Sun, 28 Jul 2019 05:40:09 -0700 by scuzzo84

JPA3 -- Two-way and Cascade Operations

JPA3 - Two-way and Cascade Operations One-way one-to-many 1.1 Configuration Configure onetomany on one side @Entity @Table(name="t_productDir") public class ProductDir { @Id @GeneratedValue private Long id; private String name; //Configure Multi-party List/Set @OneToMany(f ...

Posted on Sun, 28 Jul 2019 03:11:31 -0700 by ThermalSloth

python uses MYSQL database

The database will be used for testing. Today, I write an article about connecting MYSQL database through python.   What is MYSQL database MySQL is a relational database management system, developed by Swedish MySQL AB Company, and currently belongs to Oracle's products. MySQL is one of the most popular relational database management systems. ...

Posted on Sat, 27 Jul 2019 00:54:47 -0700 by pgsjoe