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preface Beijing Renmin Jincang Information Technology Co., Ltd. (hereinafter referred to as "Renmin Jincang") is a domestic data management software and service provider with independent intellectual property rights. Founded in 1999 by a group of experts from Renmin University of China who are the first to carry out database teaching, ...

Basic principles of ChainlinkIn this paper, we will briefly introduce the basic principle of Chainlink. If we use the shortest sentence to explain what Chainlink is, we can say that Chainlink is a decentralized Oracle project, so in order to understand the working principle of Chainlink, we should first understand what is a oracle. Prophecy mac ...

Mongodb's export mongodump is used in combination with mongorestore import tool. Can be used for database backup and restore. mongodump is a utility for creating binary exports of database content. mongodump can export data from mongod or mongos instances; that is, it can export data from independent, replica set and shard cluster deployment.I ...

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 ...

1 software environment Oracle Linux 6.9 Oracle Enterprise Manager Cloud Control 12.1.0.4 Oracle 11.2.0.3 2 software preparation 1) Download EM database template https://www.oracle.com/enterprise-manager/downloads/cloud-control-downloads.html 2) Download Oracle Enterprise Manager Cloud Control 12.1.0.4 https://www.oracle.com/enterprise- ...

Traditional jdbc Code: package com; import java.sql.*; /** * @author liuyj * @Title: JdbcTest * @create 2020-05-27 17:31 * @ProjectName algorithm-Exercise * @Description: TODO */ public class JdbcTest { public static void main(String[] args) { Connection connection=null; PreparedStatement preparedStatement=null; ...

Use Grafana and Prometheus to monitor the performance of Linux server, mainly through node_ The exporter monitors, such as CPU, memory, disk, etc. Prometheus collects data from remote machines through HTTP protocol and stores Prometheus local timing database. Install startup node_exporterNode needs to be installed on the monitored server_ exp ...

In MySQL, there are many powerful tools, such as mysql, mysqladmin, mysqldump, etc.1. mysql commandThe Mysql command is the most common command tool used to provide a command line interface for users to operate and manage MySQL servers.You can see how it's used in more detail through mysql --help.1) Grammar used for -e, -u, -p, -h, -P, and so ...

Previously, we detailed the changes and additions to Oracle. Today let's go on to learn more about Oracle's queries. Queries in Oracle are a big deal!!! Follow the steps of brilliant sir, move, move ~~   Small bag of knowledge Before that, let's talk about a little bit of Oracle commentary, which is very helpful for our development, oh!!! ...

Recently, I had to implement universal unique identifiers (UUIDs) in Laravel 7, and encountered some problems. I hope this post can help other people who are doing the same thing. Advanced reasons for using UUIDs A) They remove the ID number from your uniform resource locator, so users can't see how many specific objects your app has created. F ...