Home Backend Development PHP Tutorial Detailed explanation of mysql database (ubuntu 14.0.4 LTS 64)

Detailed explanation of mysql database (ubuntu 14.0.4 LTS 64)

Dec 20, 2017 pm 01:28 PM
mysql ubuntu

Today I will review the concept of mysql for you and give a detailed analysis of mysql based on ubuntu 14.0.4 LTS 64-bit. Friends in need can refer to it.

1.The composition and related concepts of mysql database

First understand that mysql is a relational database, and a non-relational database The biggest difference is that the concept of table is different.

+The entire mysql environment can be understood as the largest database: A

+Database B created with mysql belongs to A and is a data warehouse, equivalent to a folder in the system

+Data table C: It is a specific place to store data, which is equivalent to a file in the system. A database B contains several data tables C (note that database B and A here are different)

+Record D: A row in the data table is called a record. Therefore, when we create the data table, we must create an id column to identify "which record is this". The values ​​of the id column cannot be the same. It must be unique, just like an ID number. There can be multiple records in a table C D

+Field E: Each column in a table is called a "field". Each field in the database has regulations, such as: field Data type, empty or not empty judgment, automatic growth, etc. A record D can have multiple fields E.

+Data F: The intersection of rows and columns is the real "data" F.

2. Examples of common commands for basic database operations (ubuntu environment).

2.1 Log in to mysql: mysql-uroot-p-u: Log in with user name, -p: Enter password


2.2 View the database: After entering the above command You will be asked to enter a password. After successful login, the interface as shown above will be displayed. View the data B

showdatabases that comes with system A; pay attention to the semicolon. The database that comes with the system is shown in the figure below.


2.3 Create database: create database mytest; This creates a database B with the name of mytest.


2.4 Among the above four databases, how to choose the database we want? usemytest, this will select our database mytest.


2.5 If you want to delete the database: dropdatabasemytest will delete the database without prompting.

2.6 Check the current status: status;


##2.7 Display table C in the current database. There are two ways below. a:showtables;b:showtablesFROMmytest;.where mytest is the database we established.


2.8 Creation and deletion of data tables

createtablemytable(idint,nameint);

droptablemytable;


2.9 How to use the established data table, that is, how to

insert data into the data table? insertintomytable(id,name)values(1,10);

2.10 Query the data in the table, selectid, namefrommytablewhereid=1order; or select*frommytable


2.11 Update the data in the table, update mytable set name=20 where id=1;


2.12 Delete the table: deletefrommytable; or droptablemytable;

2.13 Modification of table structure

(1) Add a field format:

altertabletable_nameaddcolumn (field name field type); --- This method has brackets

(2) Specify the field Inserted position:

altertabletable_nameaddcolumn field name field type after a certain field;

(3) Modify field name/type

altertabletable_namechange old field name new field name new field type ;

(4) Change the name of the table

altertabletable_namerenametonew_table_name;

(5) Clear all the data in the table at one time

truncatetabletable_name;This method also Will cause the number picker (ID) in the table to start from 1

(6) Delete a field:

altertabletable_namedrop field name;

2.14 Modify password format: mysqladmin- uusername -p old password password new password;

2.15 Display the structure of the table: describemytables;


2.16 Display the current database and user show database( ); show user();


3 Note:

3.1 If you find that you forgot to add a semicolon after pressing Enter when typing the command, you do not need to repeat it. Type the command again, just hit a semicolon and press Enter.

3.2 You can use the cursor up and down keys to call up previous commands.


# I believe you have mastered the methods after reading these cases. For more exciting information, please pay attention to other related articles on the php Chinese website!

Related reading:

AJAX implementation of simple registration page asynchronous request example code

Using jQuery+Ajax in PHP Paging query function

Detailed example of ajax implementation of uploading files without refreshing

The above is the detailed content of Detailed explanation of mysql database (ubuntu 14.0.4 LTS 64). For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

MySQL: An Introduction to the World's Most Popular Database MySQL: An Introduction to the World's Most Popular Database Apr 12, 2025 am 12:18 AM

MySQL is an open source relational database management system, mainly used to store and retrieve data quickly and reliably. Its working principle includes client requests, query resolution, execution of queries and return results. Examples of usage include creating tables, inserting and querying data, and advanced features such as JOIN operations. Common errors involve SQL syntax, data types, and permissions, and optimization suggestions include the use of indexes, optimized queries, and partitioning of tables.

How to open phpmyadmin How to open phpmyadmin Apr 10, 2025 pm 10:51 PM

You can open phpMyAdmin through the following steps: 1. Log in to the website control panel; 2. Find and click the phpMyAdmin icon; 3. Enter MySQL credentials; 4. Click "Login".

Why Use MySQL? Benefits and Advantages Why Use MySQL? Benefits and Advantages Apr 12, 2025 am 12:17 AM

MySQL is chosen for its performance, reliability, ease of use, and community support. 1.MySQL provides efficient data storage and retrieval functions, supporting multiple data types and advanced query operations. 2. Adopt client-server architecture and multiple storage engines to support transaction and query optimization. 3. Easy to use, supports a variety of operating systems and programming languages. 4. Have strong community support and provide rich resources and solutions.

MySQL's Place: Databases and Programming MySQL's Place: Databases and Programming Apr 13, 2025 am 12:18 AM

MySQL's position in databases and programming is very important. It is an open source relational database management system that is widely used in various application scenarios. 1) MySQL provides efficient data storage, organization and retrieval functions, supporting Web, mobile and enterprise-level systems. 2) It uses a client-server architecture, supports multiple storage engines and index optimization. 3) Basic usages include creating tables and inserting data, and advanced usages involve multi-table JOINs and complex queries. 4) Frequently asked questions such as SQL syntax errors and performance issues can be debugged through the EXPLAIN command and slow query log. 5) Performance optimization methods include rational use of indexes, optimized query and use of caches. Best practices include using transactions and PreparedStatemen

How to connect to the database of apache How to connect to the database of apache Apr 13, 2025 pm 01:03 PM

Apache connects to a database requires the following steps: Install the database driver. Configure the web.xml file to create a connection pool. Create a JDBC data source and specify the connection settings. Use the JDBC API to access the database from Java code, including getting connections, creating statements, binding parameters, executing queries or updates, and processing results.

How to start mysql by docker How to start mysql by docker Apr 15, 2025 pm 12:09 PM

The process of starting MySQL in Docker consists of the following steps: Pull the MySQL image to create and start the container, set the root user password, and map the port verification connection Create the database and the user grants all permissions to the database

MySQL's Role: Databases in Web Applications MySQL's Role: Databases in Web Applications Apr 17, 2025 am 12:23 AM

The main role of MySQL in web applications is to store and manage data. 1.MySQL efficiently processes user information, product catalogs, transaction records and other data. 2. Through SQL query, developers can extract information from the database to generate dynamic content. 3.MySQL works based on the client-server model to ensure acceptable query speed.

How to install mysql in centos7 How to install mysql in centos7 Apr 14, 2025 pm 08:30 PM

The key to installing MySQL elegantly is to add the official MySQL repository. The specific steps are as follows: Download the MySQL official GPG key to prevent phishing attacks. Add MySQL repository file: rpm -Uvh https://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm Update yum repository cache: yum update installation MySQL: yum install mysql-server startup MySQL service: systemctl start mysqld set up booting

See all articles