Shulou(Shulou.com)06/01 Report--

Overview

MySQL is an open source relational database management system (RDBMS), which uses the most commonly used database management language-structured query language (SQL) for database management.

MySQL is open source, so anyone can download it under the license of General Public License and modify it according to their individual needs.

MySQL has attracted much attention because of its speed, reliability and adaptability. Most people agree that MySQL is the best choice for managing content without the need for transactional processing.

Characteristics

1.MySQL has excellent performance and stable service, with few abnormal downtime.

2.MySQL has the advantages of open source code, no copyright restriction, autonomy and low cost.

3.MySQL has a long history and users are active. If you encounter problems, you can ask for help.

4.MySQL is small in size, easy to install and easy to maintain.

5.MySQL word-of-mouth effect is good, is the enterprise does not need to consider to use it, LAMP, LNMP popular architecture.

6.MySQL supports a variety of operating systems, provides a variety of API interfaces, and supports many development languages, especially PHP.

Basic operation commands of database

DDL operation commands DML operation commands DQL operation commands DCL operation commands MySQL case

MySQL management operation

View the database structure to create records for deleting libraries and table management tables

Basic operation command

View database list information

Overview of SQL statement

SQL language

It is the abbreviation of Structured Query Language, that is, structured query language is the standard language of relational database for maintaining and managing database, such as data query, data update, access control, object management and so on.

SQL classification

DDL: data definition language

DML: data manipulation language

DQL: data query language

DCL: data control language

DDL statement operations (create, delete)

DDL statement is used to create database objects, such as libraries, tables, indexes, etc. Create database: CREATE DATABASE database name create database table: CREATE TABLE table name (field definition … )

DML statement operation

The DML statement is used to manage the data in the table

INSERT: insert new data UPDATE: update existing data DELETE: delete unwanted data

Insert a new data record into the data table

INSERT INTO table name (field, field 2, … ) VALUES (value of field 1, value of field 2, … )

Modify and update data records in the data table

UPDATE table name SET field name 1 = value 1 [, field name 2 = value 2] WHERE conditional expression

Deletes the specified data record in the data table

DELETE FROM table name WHERE conditional expression

Statements without where conditions indicate that all records in the table are deleted (proceed with caution)

Where is followed by a condition. Specify the object. If the condition is not followed, all will be deleted.

DQL statement operation DQL is a data query statement with only one item: SELECT is used to find qualified data records from a data table

1. No conditions can be specified when querying

SELECT field name 1, field name 2... FROM table name

two。 Specify conditions when querying

SELECT field name 1, field name 2... FROM table name WHERE conditional expression

3. Set user permissions (create a new user when the user does not exist)

GRANT permission list ON database name. Table name TO user name @ Source address [IDENTIFIED BY password]

4. View the user's permissions

SHOW GRANTS FOR user name @ Source address

5. Revoke the permissions of a user

REVOKE permission list ON database name. Table name FROM user name @ source address GRANT all ON bbs.* TO 'bbsuser'@'%' IDENTIFIED BY' admin123'

Source address write% represents all IP addresses

Writing all in the permission list means to release all permissions.

Table name write * represents all tables under the database

If the user name already exists, change the user password, and if the user does not exist, create the user directly

The meaning of raising the right of grant

The intention of revoke to withdraw its authority

Real fuck

Create a database

Access to the database

Create a tabl

View the contents of the table

Add the contents of the table

Adding default information cannot be empty. Use default by default if you want to.

View all the contents of the table

Change the contents of the table

Delete records from the table

Delete tabl

Delete Library

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