MySQL learning notes bronze

Database introduction What is a database: a database is a warehouse that organizes, stores and manages data according to a certain data structure Common databases         Oracle Stable operation, high portability, complete functions, excellent performance! It is suitable for large enterprises.         DB2 Fast speed, good reliability, sui ...

Posted on Sat, 28 Dec 2019 07:54:44 -0500 by gbrown

Playing with big data -- operating EXCEL of office/wps through java

To operate Office documents, you need a toolkit from apache Company: poi-3.7-20101029.jar The use of poi plug-ins is similar to dom technology   Different versions:     Next, we will demonstrate the function: 1. Create a file named a.xls (Workbook) with pure Java technology, Create a sheet of "Table 1" and ...

Posted on Fri, 27 Dec 2019 10:41:40 -0500 by svgk01

Comparison of default isolation levels between Oracle and Mysql

1, Transaction isolation 1.1 example of reading phenomenon 1.1.1 Dirty reads One transaction is allowed to read the data modified but uncommitted by another transaction. If another transaction is rolled back, the data read by the current transaction is dirty data time Transaction A Transaction B 1 SET TRANSACTION ISOLATION LEVEL READ UNCOM ...

Posted on Fri, 27 Dec 2019 03:56:34 -0500 by jdock1

Practice of ProxySQL Read-Write Automatic Separation in Database Middleware

Reference Documents https://github.com/sysown/proxysql http://www.fordba.com/mysql_proxysql_rw_split.html https://www.cnblogs.com/zhoujinyi/p/6829983.html Tencent Cloud cdb can provide the form of primary library VIP+read-only slave library VIP. As a result, two VIPs need to be maintained during development and use, and no automatic read-write ...

Posted on Thu, 26 Dec 2019 20:28:37 -0500 by vigiw

MySQL Foundation (02): Looking at table structure design from five dimensions

Source code for this article: GitHub. Click here || GitEE. Click here 1. Data Scenarios 1. Introduction to table structure Everything in the tool class is designed to solve problems in a scenario, such as Redis caching system hot spot data, ClickHouse solving real-time analysis of massive data, and MySQL relational databases storing structur ...

Posted on Thu, 26 Dec 2019 18:53:27 -0500 by afterburner

MHA High Availability Cluster for MySQL Database

Overview of MHA Japanese DeNA youshimaton (now a Facebook company) developmentA set of excellent high-availability software for failover and master-slave promotion in MySQL high-availability environment Composition of MHA MHA Manager (Management Node)MHA Node MHA features During automatic failover, MHA tries to save binary logs from the d ...

Posted on Thu, 26 Dec 2019 16:57:44 -0500 by anshu.sah

Ubuntu 18.04 install MySQL; Ubuntu root password modification; navicat connect to remote database;

Download and install MySQL Download MySQL and create the file storage path: mkdir software/data/mysql wget https://dev.mysql.com/get/mysql-apt-config_0.8.10-1_all.deb sudo apt-get update sudo apt-get install mysql-server baicun@ubuntu1:~/software/data/mysql$ sudo apt-get install mysql-server Reading package lists... Do ...

Posted on Thu, 26 Dec 2019 16:36:07 -0500 by CaptainChainsaw

MySQL data type -- date time type

In MySQL relational database, MySQL supports a lot of data types. It is mainly divided into three categories: numerical type, date time type and character type. In fact, these three types of data can be further subdivided and expanded, and the most suitable one can be selected according to the business needs. This article mainly ...

Posted on Thu, 26 Dec 2019 15:59:37 -0500 by tomwhalen

Five uses of postgresql highly available repmgr: manual failover,node rejoin of 1 Primary + 1 Standby

os: ubunbu 16.04 postgresql: 9.6.8 repmgr: 4.1.1 192.168.56.101 node1 192.168.56.102 node2 Contents of / etc/repmgr.conf before operation The contents of files on node1 node are similar to those on node2 node $ cat /etc/repmgr.conf node_id=1 node_name=node1 conninfo='host=192.168.56.101 user=repmgr dbname=repmgr connect_time ...

Posted on Thu, 26 Dec 2019 10:45:21 -0500 by Pyro4816

Real time synchronization of SQL Server CDC data to analytical dB for PostgreSQL and OSS through Kafka connect

background SQL server provides CDC mechanism for real-time update data synchronization, similar to Mysql binlog, which maintains data update operations into a CDC table.The source table that opens the cdc inserts data into the log table when inserting, updating, and deleting DELETE activities. cdc captures the change data into the change table ...

Posted on Thu, 26 Dec 2019 03:33:33 -0500 by keyboard