运算符与通配符

比较运算符和比较函数 (Comparison Functions and Operators)

https://dev.mysql.com/doc/refman/5.7/en/comparison-operators.html

Name	Description
>	Greater than operator
>=	Greater than or equal operator
<	Less than operator
<>, !=	Not equal operator
<=	Less than or equal operator
<=>	NULL-safe equal to operator
=	Equal operator
BETWEEN ... AND ...	Whether a value is within a range of values
COALESCE()	Return the first non-NULL argument
GREATEST()	Return the largest argument
IN()	Whether a value is within a set of values
INTERVAL()	Return the index of the argument that is less than the first argument
IS	Test a value against a boolean
IS NOT	Test a value against a boolean
IS NOT NULL	NOT NULL value test
IS NULL	NULL value test
ISNULL()	Test whether the argument is NULL
LEAST()	Return the smallest argument
LIKE	Simple pattern matching
NOT BETWEEN ... AND ...	Whether a value is not within a range of values
NOT IN()	Whether a value is not within a set of values
NOT LIKE	Negation of simple pattern matching
STRCMP()	Compare two strings

逻辑运算符 (Logical Operators)

https://dev.mysql.com/doc/refman/5.7/en/logical-operators.html

Name	Description
AND, &&	Logical AND
NOT, !	Negates value
OR, ||	Logical OR
XOR	Logical XOR

通配符

SELECT name FROM heros WHERE name LIKE '_%太%';

使用 LIKE 操作符

% 匹配任意字符串出现的任意次数

_ 匹配任意字符出现一次

当遇到需要转移的字符时候用 \ 进行字符的转移