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MySQL learning notes station B DAY01 1. What is a database? What is a database management system? What is SQL? What is the relationship between them? Database: English words DataBase，abbreviation DB. A combination of files that store data in a format. As the name suggests: a warehouse for storing data is actually a pile of files. Stored i ...

catalogue 1. Database foundation 2. Database and data table management 3. Simple query and data operation 4. Backup and restore database Import: - MySQL basic usage In the information society, fully and effectively managing and utilizing all kinds of information resources is the prerequisite for scientific research and decision-making m ...

_Previously, I voted for fans to find the most familiar stranger in MySQL ~~Which technical points in MySQL are you familiar with and unfamiliar with? The top three ranks are not as bad as I expected, respectively: 1. Cursors2. Window Functions3. Cluster Index _Although these three points are rarely used, they are often asked in interviews ...

Simple queries and inserted statements Simple query statement If we want to see what data has been stored in a table, we can use the following statement: SELECT * FROM Table name; For example, we want to see the first created earlier_ The data in the table can be written as follows: mysql> SELECT * FROM first_table; Empty set (0.01 sec ...

Prepare two machines with mysql installed (installed on different machines). If it is a machine for virtual machine replication, you need to modify the uuid in the / var/lib/mysql/auto.cnf file to ensure that the UUIDs of the two machines are differentBackup the data from the primary database to the standby database. The two databases are consi ...

1, Database operation 1.1 create database Using sql statements to create Syntax: create database database name charset utf8; For example, create a database named test1 create database test1;Create using the graphical interface Navicat Select connection - right click to select "New Database", enter the database name, and click ok ...

1, MHA concept 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 seconds. MHA can ensure th ...

175. Combine two tables SELECT FirstName, LastName, City, State From Person LEFT OUTER JOIN Address ON Person.PersonId = Address.PersonId; Chapter 16 of MySQL must know and know exercises related to creating advanced connections customers table and orders table [the external chain image transfer fails. The source station may have an ...

1, MMM overview 1. What is MMM   MMM (Master Master replication manager for MySQL) is a script program that supports dual master failover and dual master daily management. Mmm is developed in Perl. It mainly monitors and manages MySQL master master replication. Although it is called dual master replication, only one master is allow ...

Table 6 constraints Non NULL constraint not null DROP TABLE IF EXISTS tb_user; #If the table exists, delete it. If you use it with caution, you will lose data CREATE TABLE tb_user( id INT AUTO_INCREMENT, NAME VARCHAR(30) UNIQUE NOT NULL, age INT, phone VARCHAR(20) UNIQUE NOT NULL, email VARCHAR(30) UNIQUE NOT NULL, PRIMARY KEY ( ...