QueryWrapper 条件构造常用方法

QueryWrapper概述:

        也称条件构造器,继承自AbstractWrapper,自身的内部属性entity,也用于生成where条件及LambdaQueryWapper,可以通过new QueryWrapper().lambda()方法获取

QueryWrapper wrapper = new QueryWrapper<>()

QueryWrapper常见用法

函数名	说明	例子
eq	等于 =	eq("name","海绵宝宝")  →  name="海绵宝宝"
ne	不等于 <>	ne("name","海绵宝宝")  →  name<>"海绵宝宝"
gt	大于 >	gt("age","18")   →  age>18
ge	大于等于 >=	ge("age","18")  →  age>=18
le	小于等于 <=	le("age","18")  →  age<=18
lt	小于 <	lt("age","18")  →  age<18
between	BETWEEN 值1 and 值2	between("age",18,30)  →  age between 18 and 30
notBetween	NOT BETWEEN 值1 and 值2	between("age",18,30)  →  age not between 18 and 30
like	LIKE '%值%'	like("name","海")  →  name like "%海%"
notLike	NOT LIKE '%值%'	not like("name","海")  →  name like "%海%"
likeLeft	LIKE '%值'	leftLlike("name","海")  →  name like "%海"
likeRight	LIKE '值%'	rightLlike("name","海")  →  name like "海%"
isNull	字段 IS NULL	isNull("name")  →  name is null
isNotNull	字段 IS NOT NULL	is Not Null("name")  →  name is not null
in	字段 IN(v0,v1,v2,...)	in("age",{1,2,3})  →  age in (1,2,3)
notIn	字段 NOT IN(v0,v1,v2,...)	notIn("age",{1,2,3})  →  age not in (1,2,3)
inSql	字段 IN(sql语句)	inSql("id","select id from table where id<3")
		→  age in(select id from table where id<3)
notInSql	字段 NOT IN(sql语句)	notInSql("id","select id from table where id<3")
		→  age not in(select id from table where id<3)
groupBy	分组:groupBy	groupBy("id","name")  →  group by id,name
orderByAsc	正序排序	orderByAsc("id","name")  →  order by id Asc,name Asc
orderByDesc	倒序排序	orderByDesc("id","name") → order by id Desc,name Desc
orderBy	排序  :ODER BY 字段	orderBy(true,true,"id","name")→ order by id Asc,name Asc
having	HAVING(sql语句)	having("sum(age) > {0}",11) →  having sum(age) >11
or	拼接 OR	eq("id",1).or().eq("name","派大星")
		→  id=1 or name="派大星"
and	AND 嵌套	用于嵌套
apply	拼接 sql	用于数据库函数,一般having很少用
last	无视化规则直接拼接到sql的最后	只能调用一次  last("limit 1")
exists	拼接EXISTS(sql语句)	exists("select id from table where age = 1")
		→exists("select id from table where age = 1")
notExists	拼接NOT EXISTS(sql语句)	notExists("select id from table where age = 1")
		→not exists("select id from table where age = 1")