Method usage and introduction of QueryWrapper

1. eq、ne   

    【 等于】 wrapper.eq("last_name", "values"); -> sql 语句 where last_name ="values"

       【不等】 wrapper.ne("last_name", "values"); -> sql 语句 where last_name !="values"

2 .gt、ge、lt、le

       【大于】 wrapper.gt("last_name", "values"); -> sql 语句 where last_name >"values"

       [Greater than or equal to] wrapper.ge("last_name", "values"); -> sql statement where last_name>="values"

       【小于】 wrapper.lt("last_name", "values"); -> sql 语句 where last_name <"values"

       [Less than or equal to] wrapper.le("last_name", "values"); -> SQL statement where last_name <="values"

3.between、notBetween

[between a and b]

      wrapper.between("last_name",a,b) -> sql 语句 where last_name (between a and b);

[not between a and b]

 wrapper.notBetween("last_name",a,b) -> sql 语句 where last_name (Not between a and b);

4.like、notLike、likeLeft、likeRight

[Field value includes] wrapper.like("last_name","v") -> sql statement where last_name like %v%;

[Field value does not include] wrapper.notlike("last_name","v") -> sql statement where last_name notlike %v%;

[Match at the beginning of the field value]

        wrapper.likeLeft("last_name","v") -> sql 语句 where last_name  notlike %v;

[Field value end match]

        wrapper.notlike("last_name","v") -> sql 语句 where last_name  notlike  v%;

5.isNull、isNotNull

[Field value is empty] wrapper.isNull("last_name") -> sql statement where last_name is null;

[Field value is not empty] wrapper.isNotNull("last_name") -> sql statement where last_name is not null;

6.in、notIn

[Field value is within the interval]

         wrapper.in("last_name",a,b,c) -> sql 语句 where last_name in(a,b,c)；

[Field value is not within the range]

        wrapper.notin("last_name",a,b,c) -> sql 语句 where last_name not in(a,b,c)；

7.or、and

[Multiple conditions]

           wrapper.notin("last_name",a,b,c).or().eq("name","aa");

-> sql 语句 where last_name not in(a,b,c) or name  = "aa"；

   wrapper.notin("last_name",a,b,c).and().eq("name","aa");

-> sql 语句 where last_name not in(a,b,c) and name  = "aa"；

8.orderByAsc、orderByDesc

       [Positive order] Wrapper.orderByAsc("id"); -> sql statement orderByAsc "id" 

       [Reverse order] Wrapper.orderByDesc("id"); -> sql statement orderByDesc "id"