--第一章上机 --创建BBS数据库 create database 库名 on primary//建数据库文件 ( name库名_mdf, filename='路径', size=初始大小, maxsize=unlimited-表示无限制增长, filegrowth=15%-按百分比来比较 ) log on建事务日志文件 ( name=BBS_ldf, filename='d:\
--第一章上机
--创建BBS数据库
create database 库名
on primary//建数据库文件
(
name库名_mdf,
filename='路径',
size=初始大小,
maxsize=unlimited-表示无限制增长,
filegrowth=15%-按百分比来比较
)
log on建事务日志文件
(
name=BBS_ldf,
filename='d:\BBSdatabase\BBS.ldf',
size=3mb,
maxsize=30mb,
filegrowth=5%
)
--删除数据库
drop database 库名
--第二章上机
--创建表的结构
use 库名
create table 新建表名
(
列名 int identity(1,1) not null primary key, --标识列、自动增长
列名 varchar (16) not null default('888888'), --不为空、默认值
列名 datetime, --日期用datetime表示
列名 varchar(13) not null unique check (len(列名)=15 or len(列名)=18),
列名 varchar(50) not null check(列名 Like '表达式' or len(列名)=11)
列名 varchar(20) not null foreign key references 引用主键表(对应的列名)
)
--创建已有的表的约束
Alter table 存在的表名
Add constraint 约束名称 check(len(UPassword)>=6),
constraint CK_id check(UEmail like '%@%')
--建立已有表之间的主外键关系
Alter table 表名
add constraint 约束名称 foreign key (子表列名) references 主表名称(对应的主表列名),
constraint FK_TUID foreign key (TUID) references BBSUsers(UID)
……
--创建数据库关系图
--点击数据关系图,右键创建新的关系图,按CTRL选择全部的表即可
--向表中插入数据方法一用insert向表中插入
insert into 表名(列名1,列名2,列名3,……)
values('对应列名1的值','对应列名2的值','对应列名3的值',……)
--向表中插入数据方法二用select来插入
insert into 表名(列名 1,列名2,列名3,……)
select '对应列名1的值','对应列名2的值','对应列名3的值',…… union //插入的第一行数据
select '对应列名2的值','对应列名2的值','对应列名3的值',…… union //插入的最后一行数据
…… union
select '对应列名N的值','对应列名N的值','对应列名N的值',…… 切记住最后一行没有union
--执行更新
update set [where ] //可以紧随多个数据列的更新值
--delete删除数据
delete from [where ]
--Truncae Table 删除数据 用来删除所有表中的所有行
Truncate table 表名

InnoDBBufferPool reduces disk I/O by caching data and indexing pages, improving database performance. Its working principle includes: 1. Data reading: Read data from BufferPool; 2. Data writing: After modifying the data, write to BufferPool and refresh it to disk regularly; 3. Cache management: Use the LRU algorithm to manage cache pages; 4. Reading mechanism: Load adjacent data pages in advance. By sizing the BufferPool and using multiple instances, database performance can be optimized.

Compared with other programming languages, MySQL is mainly used to store and manage data, while other languages such as Python, Java, and C are used for logical processing and application development. MySQL is known for its high performance, scalability and cross-platform support, suitable for data management needs, while other languages have advantages in their respective fields such as data analytics, enterprise applications, and system programming.

MySQL is worth learning because it is a powerful open source database management system suitable for data storage, management and analysis. 1) MySQL is a relational database that uses SQL to operate data and is suitable for structured data management. 2) The SQL language is the key to interacting with MySQL and supports CRUD operations. 3) The working principle of MySQL includes client/server architecture, storage engine and query optimizer. 4) Basic usage includes creating databases and tables, and advanced usage involves joining tables using JOIN. 5) Common errors include syntax errors and permission issues, and debugging skills include checking syntax and using EXPLAIN commands. 6) Performance optimization involves the use of indexes, optimization of SQL statements and regular maintenance of databases.

MySQL is suitable for beginners to learn database skills. 1. Install MySQL server and client tools. 2. Understand basic SQL queries, such as SELECT. 3. Master data operations: create tables, insert, update, and delete data. 4. Learn advanced skills: subquery and window functions. 5. Debugging and optimization: Check syntax, use indexes, avoid SELECT*, and use LIMIT.

MySQL efficiently manages structured data through table structure and SQL query, and implements inter-table relationships through foreign keys. 1. Define the data format and type when creating a table. 2. Use foreign keys to establish relationships between tables. 3. Improve performance through indexing and query optimization. 4. Regularly backup and monitor databases to ensure data security and performance optimization.

MySQL is an open source relational database management system that is widely used in Web development. Its key features include: 1. Supports multiple storage engines, such as InnoDB and MyISAM, suitable for different scenarios; 2. Provides master-slave replication functions to facilitate load balancing and data backup; 3. Improve query efficiency through query optimization and index use.

SQL is used to interact with MySQL database to realize data addition, deletion, modification, inspection and database design. 1) SQL performs data operations through SELECT, INSERT, UPDATE, DELETE statements; 2) Use CREATE, ALTER, DROP statements for database design and management; 3) Complex queries and data analysis are implemented through SQL to improve business decision-making efficiency.

The basic operations of MySQL include creating databases, tables, and using SQL to perform CRUD operations on data. 1. Create a database: CREATEDATABASEmy_first_db; 2. Create a table: CREATETABLEbooks(idINTAUTO_INCREMENTPRIMARYKEY, titleVARCHAR(100)NOTNULL, authorVARCHAR(100)NOTNULL, published_yearINT); 3. Insert data: INSERTINTObooks(title, author, published_year)VA


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

Notepad++7.3.1
Easy-to-use and free code editor

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

Dreamweaver CS6
Visual web development tools