Mysql first day, mysql first day

Mysql first day, mysql first day

1. Data Warehouse. just like the plain text, properties, and XML technologies we have learned before. used to save data. it also allows you to add, delete, modify, and query data. when we are working on a project later,

Project data is stored in the database.

2. database features

2.1 data sharing
2.2 reduce data redundancy

2.3 centralized data control

2.4 data consistency, integrity and maintainability to ensure data security and reliability

2.5 fault recovery

3. Install Mysql

There are two installation locations.

Database Service Location: MySQL Server
Database data File Location: Server data files

The mysql Database Administrator name is root.

4. FAQs:
4.1. uninstall mysql.
4.1.1 run the uninstall program
4.1.2. delete a directory
4.2 forgot to configure character set encoding during installation
The configuration during installation will be reflected in the my. ini file. The file is located in the path of the database service. Find the configuration file to modify and save. To take effect, restart the database (restart the service ).
4.3. Forget the administrator password. = See the method in the resource folder.
4.4. You forgot to check the auto-configure environment variable option.
Find the bin directory under the database service installation directory. Configure the directory path to the path environment variable.
4.5 install the new version of mysql, prompting you to install framework 4.0.

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5. SQL

DDL database Definition Language Data Definition Language | create alter drop
DCL Database Control Language Data Control Language | grant rollback commit.
DML database operating Language Data Manipulation Language | insert update delete select
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DQL Database Query Language Data Query Language | select

6. Notes in SQL
Single Row :--
Multiple rows :/**/
Is SQL case insensitive?
The statement is case insensitive.
The data is case sensitive.
";" Indicates the end of SQL statement in mysql.

Exit command => exit

Database Service commands

Mysql-u root-p

Enter the password as prompted to establish a connection.