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Environmental Science OS: Ubuntu20.04 MongoDB: v5.0.2 Introduction to MongoDB MongoDB is an open source document database that provides high performance, high availability, and automatic scaling to provide scalable high performance data storage solutions for WEB applications. MongoDB is a product between relational and non-relational datab ...

After nearly two years of optimization and polishing, Apache shardingsphere version 5.0.0 GA was finally officially released this month. Compared with version 4.1.1 GA, version 5.0.0 GA has been greatly optimized at the kernel level. Firstly, the kernel is completely transformed based on the pluggable architecture, and various functions in the ...

Author: Zhang Lianzhuang, PostgreSQL R & D EngineerHe has been engaged in the development of PostgreSQL database kernel for many years and has a very in-depth research on citus.Last issue We introduced the PostgreSQL data retrieval tool: pg_reconveryThis article will take you to understand PG_ The implementation principle and design idea of ...

1, Introduction 1. What is Room The room framework is one of many component libraries of Android Jetpack. The emergence of Jetpack unifies the Android development ecology, various tripartite libraries are gradually replaced by official components, and room gradually replaces competitive products as the most mainstream database ORM framewo ...

# database understanding MySQL DB Database, container for storing data DEMS Database management system, also known as database software or database products, is used to create or manage DB SQL Structured query language, the language used to communicate with the database, is not unique to a database software, but a common language for ...

1. What is a database connection pool Why use connection pooling: When we develop in Java, we need to access the database, but Java can't access the database directly. We have to establish a connection between the program and the database through JDBC. Performing a transaction requires creating a connection. The process of establishing a co ...

        This database exercise is a part of hands-on operation after I summarized the database knowledge points released last time. The focus is to deepen the understanding of the database. In the face of the preparation of sentences, colleagues can criticize and correct more. 1. Create database tables. CREATE DATABASE sch ...

Hello, everyone. I'm Mr. Tony, who only talks about technology and doesn't cut his hair. Changing the database user password on a regular basis may result in the interruption of the application. Usually, we need to plan downtime, modify the database user password, then modify the connection information in the application server, and finally re ...

This note is the learning content of Alibaba cloud Tianchi Longzhu plan SQL training camp. The link is: https://tianchi.aliyun.com/specials/promotion/aicampsql preface This note is the learning content of Alibaba cloud Tianchi Longzhu plan SQL training camp. The link is: https://tianchi.aliyun.com/specials/promotion/aicampsql 1. Part ...

12. SQL triggers MySQL triggers, like stored procedures, are a program embedded in MySQL. Triggers are events that trigger an action, including INSERT, UPDATAE, and DELETE statements. If triggers are defined, they will be triggered when the database executes these statements to perform the appropriate actions. A trigger is a named database obj ...