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I. preparation before installation 1. Check whether mysql has been installed and execute the command [root@localhost /]# rpm -qa | grep mysql From the execution results, we can see that mysql-libs-5.1.73-5.el6 has been installed_ 6.x86_ 64. Execute the delete command [root@localhost /]# rpm -e --nodeps mysql-libs-5.1.73-5.el6_6.x86_64 ...

In mysql, a set of tables is called a database. The MySQL server manages several databases. There can be several tables under each database. Draw a diagram as follows:   Display database When we just installed MySQL, many databases and tables were built in it. We can use the following command to see which databases are available: SHOW ...

1, Introduction I happened to see the domestic database - Dameng database. Suddenly became interested and made a fuss. The following introduction is taken from Baidu Encyclopedia Dameng database is a high-performance database product with completely independent intellectual property rights launched by Wuhan Huagong Dameng database Co., Ltd. ...

Introduction concept DB: databaseDBMS: Database Management SystemSQL: Structured Query Languagedatabasedata sheetfield After mysql is successfully installed, common commands: mysql [-h host ip -p port] - u user name - p enter enter password to log inshwo databases; Display all databases after successful loginuse database name; Open data ...

According to the query criteria, there are also some details to pay attention to in updating, so here we are going to update the details for your own use in the future. mongodb native db.<collection>.updateOne(filter, update, [options]); db.<collection>.updateMany(filter, update, [options]); Copy code Filter filter conditio ...

Install database - connect your computer host - create database 1, Database design 1. How to represent the relationship between databases in database design? relational model 2. What are the relationships between entity sets X and Y? One to many, one to one, many to one, many to many 3. What are the functions of the three paradigms of database ...

preface                  The main purpose of backup is disaster recovery. Backup can also test applications, rollback data modification, query historical data, audit, etc. Log plays an important role in backup and recovery. 1, MySQL log The default location of MySQL logs is / usr/local/mysq ...

1, Understanding MHA 1. When is MHA MHA (MasterHigh Availability) is a set of excellent software for failover and master-slave replication in MySQL high availability environment. The emergence of MHA is to solve the problem of MySQL single point. During MySQL failover, MHA can automatically complete the failover operation within 0-30 seco ...

1. Introduction to Redis Redis is an open source NoSQL database written in C.Redis runs in memory and supports persistence (storage on disk). It uses key-value storage as an indispensable part of the current distributed architecture.Redis server program is a single process modelRedis services can start multiple Redis processes simultaneo ...

Basic concepts DB:DataBase (database, which actually exists as a file on the hard disk) DBMS: DataBase Management System MySQL Oracle SQL: structured query language, is a standard general language. When the SQL statement is executed, it will actually be compiled internally before executing the SQL. DBMS is responsible for executing SQL stateme ...