MybatisPlus常用条件查询器Wrapper的使用

allEq(全部eq)

// 查询名字为Tom，年龄为28,邮箱为空的人
QueryWrapper<User> queryWrapper = new QueryWrapper<>();
Map<String,Object> map = new HashMap<>();
map.put("name","Tom");
map.put("age",28);
map.put("email",null);
queryWrapper.allEq(map);
// 如果第二个参数填写false，则会忽略value值为null的元素，不进行sql拼接
// queryWrapper.allEq(map,false);
userMapper.selectList(queryWrapper).forEach(System.out::println);

eq（=）

// 查询年龄为20
QueryWrapper<User> queryWrapper = new QueryWrapper<>();
queryWrapper.eq("age",20);
userMapper.selectList(queryWrapper).forEach(System.out::println);

ne(<>)

// 查询年龄不为20
QueryWrapper<User> queryWrapper = new QueryWrapper<>();
queryWrapper.ne("age",20);
userMapper.selectList(queryWrapper).forEach(System.out::println);

gt(>)

// 查询年龄大于20
queryWrapper.gt("age",20);

ge(>=)

// 查询年龄大于等于20
queryWrapper.ge("age",20);

lt(<)

// 查询年龄小于20
queryWrapper.lt("age",20);

le(<=)

// 查询年龄小于等于20
queryWrapper.le("age",20);

between

// 查询年龄10到20之间
queryWrapper.between("age",10,20);

notBetween

// 查询年龄不在10到20之间
queryWrapper.notBetween("age",10,20);

like

// 查询名字中有T的(name like '%T%')
queryWrapper.like("name","T");

notLike

// 查询名字中没有有T的(name not like '%T%')
queryWrapper.notLike("name","T");

likeLeft

// 查询名字中最后一位是T的(name like '%T')
queryWrapper.likeLeft("name","T");

likeRight

// 查询名字中第一位是T的(name like 'T%')
queryWrapper.likeRight("name","T");

isNull

// 查询名字为空的
queryWrapper.isNull("name");

isNotNull

// 查询名字不为空的
queryWrapper.isNotNull("name");

in

// 查询年龄在（20,21,22）范围内的
queryWrapper.in("age",20,21,22);

notIn

// 查询年龄不在（20,21,22）范围内的
queryWrapper.notIn("age",20,21,22);

inSql

inSql("age", "1,2,3,4,5,6")--->age in (1,2,3,4,5,6)
// 里面可以是一个sql的形式    
inSql("id", "select id from table where id < 3")--->id in (select id from table where id < 3)    

notInSql

notInSql("age", "1,2,3,4,5,6")--->age not in (1,2,3,4,5,6)
// 里面可以是一个sql的形式    
notInSql("id", "select id from table where id < 3")--->id not in (select id from table where id < 3)    

groupBy(分组)

groupBy("id", "name")--->group by id,name

orderByAsc(升序)

orderByAsc("id", "name")--->order by id ASC,name ASC

orderByDesc(降序)

orderByDesc("id", "name")--->order by id DESC,name DESC

orderBy(排序)

orderBy(true, true, "id", "name")--->order by id ASC,name ASC