UNWIND 将一个列表展开为一个行的序列
// 指定一个集合,行展开
unwind [1,2,3] as x
return x
//集合去重
with [1,1,2,2] as coll
unwind coll as x
with distinct x
return collect(x) as set
union 用于将多个查询结果组合起来
--查询到的列名和列数必须完全一致
-- all union 会包含所有结果。而 union 会去重
match (u:User{id:1})
return u.name as name
union all
match (o:User{id:8})
return o.name as name