mysql必知必会读书笔记（1/5） 前言-第8章

mysql必知必会下载地址

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链接: https://pan.baidu.com/s/1dFF6NNb 密码: d2w3

linux mint:

sudo apt install mysql-servermysql -u root -pmysql> create database book_mysql;mysql> use book_mysql;mysql> source create.sql;mysql> source populate.sql;

前言-第八章相关命令

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1. 无
2. 无
3. 
mysql -u root -p
mysql> use book_mysql;
mysql> show databases;
mysql> show tables;
mysql> show COLUMNS from customers;

   4.
mysql> select prod_id from products;
mysql> select prod_id, prod_name from products;
mysql> select * from products;
mysql> select distinct prod_id from products;
mysql> select prod_id from products limit 5;
mysql> select prod_id from products limit 5, 5;#从0开始计数

   5.
mysql> select prod_name from products order_by prod_name;
mysql> select prod_name from products order_by prod_name, prod_id;
mysql> select prod_name from products order_by prod_name disc,
prod_id;

   6.
mysql> select prod_name, prod_price from products where prod_price = 2.50;
mysql> select prod_name, prod_price from products where prod_price between 5 and 10;
mysql> select prod_name from products where prod_price is null;

   7.
mysql> select prod_name, prod_price from products where vend_id in (1002, 1003) order by prod_name;
mysql> select prod_name, prod_price from products where vend_id not in (1002, 1003) order by prod_name;

   8.无

总结

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1. 无
2. 无
3. 无
4. limit 5，为5行；limit 5，5为从第6行开始算往下数5行
5. 默认的order_by排序为asc顺序排序，指定desc则为倒序排序
6. 1.where操作符： =, !=, >, <，>=, <=, BETWEEN
   2.where匹配不区分大小写（命令同样不区分大小写，列也一样，但是数据库名和表名区分大小写）
7. 1.逻辑操作符： AND, OR, IN, NOT
   2.AND的计算优先级比OR高
8. 1.like操作符用于通配符
   2.%为匹配任意个任意字符， _为匹配1个任意字符