MySql的like语句中的通配符：百分号、下划线和escape

MySql的like语句中的通配符：百分号、下划线和escape

%代表任意多个字符
Sql代码    www.2cto.com 
select * from user where username like '%huxiao';  
 
select * from user where username like 'huxiao%';  
 
select * from user where username like '%huxiao%';  

_代表一个字符
Sql代码 
select * from user where username like '_';  
 
select * from user where username like 'huxia_';  
 
select * from user where username like 'h_xiao';  

如果我就真的要查%或者_，怎么办呢？使用escape，转义字符后面的%或_就不作为通配符了，注意前面没有转义字符的%和_仍然起通配符作用
Sql代码 
select username from gg_user where username like '%xiao/_%' escape '/';  
 
select username from gg_user where username like '%xiao/%%' escape '/';