概述

函数listUnion()计算两个列表的全部元素去重后构成的列表。类似并集，不允许有重复元素。

参数：listUnion(<list_1>, <list_2>)

• <list_1>和<list_2>：两个列表（list类型）

返回值：

• 两个列表的所有元素去重后构成的列表（list类型）

一般用法

本例使用异源别名计算：

uncollect [[1,2,2],[2,4,5]] as a
uncollect [[2,4,7],[4,5,7]] as b
return table(toString(a), toString(b), toString(listUnion(a, b)))

| toString(a) | toString(b) | toString(listUnion(a, b)) |
|-------------|-------------|---------------------------|
| [1,2,2]     | [2,4,7]     | [1,2,4,7]                 |
| [2,4,5]     | [4,5,7]     | [2,4,5,7]                 |

本例将异源别名做笛卡尔积组合后计算：

uncollect [[1,2,2],[2,4,5]] as a
uncollect [[2,4,7],[4,5,7]] as b
with listUnion(a, b) as c
return table(toString(a), toString(b), toString(c))

| toString(a) | toString(b) | toString(c) |
|-------------|-------------|-------------|
| [1,2,2]     | [2,4,7]     | [1,2,4,7]   |
| [1,2,2]     | [4,5,7]     | [1,2,4,5,7] |
| [2,4,5]     | [2,4,7]     | [2,4,5,7]   |
| [2,4,5]     | [4,5,7]     | [2,4,5,7]   |

示例图集：

在一个空图集中，依次运行以下各行语句创建示例图集：

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}])

本例查找选择了法语课或数学课的学生：

khop().src({name == "French"}).depth(1) as n1
with collect(n1) as l1
khop().src({name == "Math"}).depth(1) as n2
with collect(n2) as l2
return listUnion(l1, l2)

[
  {"id":"","uuid":"1","schema":"student","values":{}},
  {"id":"","uuid":"2","schema":"student","values":{}},
  {"id":"","uuid":"3","schema":"student","values":{}},
  {"id":"","uuid":"4","schema":"student","values":{}},
  {"id":"","uuid":"5","schema":"student","values":{}}
]