ORDER BY 可以调整别名中行与行之间的顺序。
语法:ORDER BY <expression>
<string>
, <expression>
<string>
, ...
参数:
- <expression>:排序依据,多个依据必须同源,从左到右进行逐级排序
- <string>:排序方式,'ASC' 或 'DESC',大小写均可,省略时为 'ASC' 升序
例如,对一步路径 path 进行排序,先按照终点 n 的半径降序排列,半径相同的再按照终点 n 的 _uuid
升序排列:
n([4, 2]).e().n(as n) as path
order by n.radius desc, n
return path
示例图集:(以下示例将在本图基础上运行)
在空图集中依次运行以下各行代码以创建该图数据:create().node_schema("student").node_schema("course")
create().node_property(@*, "name").node_property(@student, "age", int32).node_property(@course, "credit", int32)
insert().into(@student).nodes([{_id:"S001", _uuid:1, name:"Jason", age:25}, {_id:"S002", _uuid:2, name:"Lina", age:23}, {_id:"S003", _uuid:3, name:"Eric", age:24}, {_id:"S004", _uuid:4, name:"Emma", age:26}, {_id:"S005", _uuid:5, name:"Pepe", age:24}])
insert().into(@course).nodes([{_id:"C001", _uuid:6, name:"French", credit:4}, {_id:"C002", _uuid:7, name:"Math", credit:5}])
insert().into(@default).edges([{_uuid:1, _from_uuid:1, _to_uuid:6}, {_uuid:2, _from_uuid:2, _to_uuid:6}, {_uuid:3, _from_uuid:3, _to_uuid:6}, {_uuid:4, _from_uuid:2, _to_uuid:7}, {_uuid:5, _from_uuid:3, _to_uuid:7}, {_uuid:6, _from_uuid:4, _to_uuid:7}, {_uuid:7, _from_uuid:5, _to_uuid:7}])
分组、排序
示例:查询 1 步路径 课程-学生,按课程分组统计组内学生数量,再按学生数量降序排列
n({@course} as a).e().n({@student})
group by a
with count(a) as b
order by b desc
return table(a.name, b)
| a.name | b |
|--------|---|
| Math | 4 |
| French | 3 |
多级排序
示例:查询 1 步路径 课程-学生,按课程 credit 升序排列,再按学生 age 降序排列,携带全部属性
n({@course} as a).e().n({@student} as b) as p
order by a.credit, b.age desc
return p{*}
French <---- Jason
French <---- Eric
French <---- Lina
Math <---- Emma
Math <---- Eric
Math <---- Pepe
Math <---- Lina