search
HomeDatabaseMysql TutorialMySQL学习笔记2:数据库的基本操作_MySQL

bitsCN.com

我们所安装的MySQL说白了是一个数据库的管理工具,真正有价值的东西在于数据

关系型数据库的数据是以表的形式存在的,N个表汇总在一起就成了一个数据库

现在来看看数据库的基本操作

无非就是三点:创建 删除 查看

 

创建数据库
mysql> create database school;Query OK, 1 row affected (0.00 sec)

creare database语句用于创建数据库

后面的school是数据库的名字,分号结束

执行成功则会显示Query OK,还有执行时间

有了数据库之后,一般情况下会查看当前数据库

 

查看数据库
mysql> show databases;+--------------------+| Database           |+--------------------+| information_schema || mysql              || performance_schema || school             || test               |+--------------------+5 rows in set (0.00 sec)

这样便显示了创建的数据库,其中school是刚刚创建的

其余几个默认存在,不要乱动

test是给你做测试使用,可以删除

 

删除数据库
mysql> drop database school;Query OK, 0 rows affected (0.00 sec)

删除也很简单,drop database 命令即可

接下来就可以使用show databases查看效果

要注意的是语句后面不要忘记分号

 

在实际中,我们操作更多的不是数据库,而是数据库中的表

所以这里的内容显得很简单

 

bitsCN.com
Statement
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
How does MySQL handle concurrency compared to other RDBMS?How does MySQL handle concurrency compared to other RDBMS?Apr 29, 2025 am 12:44 AM

MySQLhandlesconcurrencyusingamixofrow-levelandtable-levellocking,primarilythroughInnoDB'srow-levellocking.ComparedtootherRDBMS,MySQL'sapproachisefficientformanyusecasesbutmayfacechallengeswithdeadlocksandlacksadvancedfeatureslikePostgreSQL'sSerializa

How does MySQL handle transactions compared to other relational databases?How does MySQL handle transactions compared to other relational databases?Apr 29, 2025 am 12:37 AM

MySQLhandlestransactionseffectivelyusingtheInnoDBengine,supportingACIDpropertiessimilartoPostgreSQLandOracle.1)MySQLusesREPEATABLEREADasthedefaultisolationlevel,whichcanbeadjustedtoREADCOMMITTEDforhigh-trafficscenarios.2)Itoptimizesperformancewithabu

How does MySQL differ from PostgreSQL?How does MySQL differ from PostgreSQL?Apr 29, 2025 am 12:23 AM

MySQLisbetterforspeedandsimplicity,suitableforwebapplications;PostgreSQLexcelsincomplexdatascenarioswithrobustfeatures.MySQLisidealforquickprojectsandread-heavytasks,whilePostgreSQLispreferredforapplicationsrequiringstrictdataintegrityandadvancedSQLf

How does MySQL handle data replication?How does MySQL handle data replication?Apr 28, 2025 am 12:25 AM

MySQL processes data replication through three modes: asynchronous, semi-synchronous and group replication. 1) Asynchronous replication performance is high but data may be lost. 2) Semi-synchronous replication improves data security but increases latency. 3) Group replication supports multi-master replication and failover, suitable for high availability requirements.

How can you use the EXPLAIN statement to analyze query performance?How can you use the EXPLAIN statement to analyze query performance?Apr 28, 2025 am 12:24 AM

The EXPLAIN statement can be used to analyze and improve SQL query performance. 1. Execute the EXPLAIN statement to view the query plan. 2. Analyze the output results, pay attention to access type, index usage and JOIN order. 3. Create or adjust indexes based on the analysis results, optimize JOIN operations, and avoid full table scanning to improve query efficiency.

How do you back up and restore a MySQL database?How do you back up and restore a MySQL database?Apr 28, 2025 am 12:23 AM

Using mysqldump for logical backup and MySQLEnterpriseBackup for hot backup are effective ways to back up MySQL databases. 1. Use mysqldump to back up the database: mysqldump-uroot-pmydatabase>mydatabase_backup.sql. 2. Use MySQLEnterpriseBackup for hot backup: mysqlbackup--user=root-password=password--backup-dir=/path/to/backupbackup. When recovering, use the corresponding life

What are some common causes of slow queries in MySQL?What are some common causes of slow queries in MySQL?Apr 28, 2025 am 12:18 AM

The main reasons for slow MySQL query include missing or improper use of indexes, query complexity, excessive data volume and insufficient hardware resources. Optimization suggestions include: 1. Create appropriate indexes; 2. Optimize query statements; 3. Use table partitioning technology; 4. Appropriately upgrade hardware.

What are views in MySQL?What are views in MySQL?Apr 28, 2025 am 12:04 AM

MySQL view is a virtual table based on SQL query results and does not store data. 1) Views simplify complex queries, 2) Enhance data security, and 3) Maintain data consistency. Views are stored queries in databases that can be used like tables, but data is generated dynamically.

See all articles

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

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

EditPlus Chinese cracked version

EditPlus Chinese cracked version

Small size, syntax highlighting, does not support code prompt function

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

ZendStudio 13.5.1 Mac

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment

SecLists

SecLists

SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.