MySql学习笔记

select version(), current_date;

select user(), current_date;

shell>mysql --help

mysql >SELECT

- >USER()

- >\c

mysql > 

//取消当前MySql语句

mysql >SELECT * FROM my_table WHERE name = 'Smith AND age < 30;

    '> '\c

mysql >

//等待完成字符（‘）或者字符串（“）

mysql >DESCRIBE pet;

//查看表的结构

mysql >LOAD DATA LOCAL INFILE '/path/pet.txt' INTO TABLE pet

- >LINES TERMINATED BY '\r\n';

// Windows

mysql >LOAD DATA LOCAL INFILE '/path/pet.txt' INTO TABLE pet

- >LINES TERMINATED BY '\r'

// MacOS

mysql >INSERT INTO pet

- >VALUES ('Puffball','Diane','hamster','f','1999-03-30',NULL);

// 数据插入

select what_to_select

from which_table

where conditions_to_satisfy;

mysql >UPDATE pet SET birth = '1989-08-31' WHERE name = 'Bowser';

mysql >SELECT * FROM pet WHERE species = 'dog' AND sex = 'f';

mysql >SELECT * FROM pet WHERE species = 'snake' OR species = 'bird';

mysql >SELECT * FROM pet WHERE (species = 'cat' AND sex = 'm')

- >OR (species = 'dog' AND sex = 'f');

mysql >SELECT name, birth FROM pet;

mysql >SELECT DISTINCT owner FROM pet;

//去重复查询

mysql >SELECT name, species, birth FROM pet

- >ORDER BY species, birth DESC;

//默认升排序，字符串使用order by binary col_name

mysql >SELECT name, birth, CURDATE(),

- >TIMESTAMPDIFF(YEAR,birth,CURDATE()) AS age

- >FROM pet;

//| name | birth | CURDATE() | age |

//| Fluffy | 1993-02-04 | 2003-08-19 | 10 |

//时间差计算

mysql >SELECT name, birth, death,

- >TIMESTAMPDIFF(YEAR,birth,death) AS age

- >FROM pet WHERE death IS NOT NULL ORDER BY age;

mysql >SELECT name, birth, MONTH(birth) FROM pet;

//查询下个月生日

mysql >SELECT name, birth FROM pet WHERE MONTH(birth) = 5;

//查询指定月份生日

mysql >SELECT name, birth FROM pet

- >WHERE MONTH(birth) = MOD(MONTH(CURDATE()), 12) + 1;

//查询下个月有生日的宠物

 “_”匹配任何单个字符 “%”匹配任意数量的字符(包括零字符)