摘要： 1.where 子句 后面可以跟 and or like > < <= >= != <> between and is null is not null in() 2.模糊查询like %:表示0个，一个，多个 _：仅代替一个字符 3.order by 排序,写在where子句后面 asc :升序， 阅读全文