ArangoDB 插入边缘不存在

Question

我想在文档集合 C1 和 C3 之间创建独特的边缘。
唯一约束是id和kid。
我使用流 aql 创建它，但我在同一个 id 和 kid 中得到了多个边。
我该如何实现？抱歉我的英语不好:)

for i in C1 filter i.id != null and i.id != '' let exist = first( for c in C2 filter i.id == c.id and i.kid == c.kid limit 1 return c ) filter exist == null let result = first( for h in C3 filter i.kid == h.kid limit 1 return h ) insert{_from:i._id, _to:result._id, id:i.id, kid:i.kid} INTO C2

Answer 1

我的英文也不太好^)！但我想，我看到你在哪里犯了错误。首先，对于您的两个 collection，您可以使用此代码：

    LET data = [
    {"parent":{"ID":"YOU_MUST_WRITE_HERE_ID_C1"},"child":{"KID":"YOU_MUST_WRITE_HERE_KID_C3"}},
    {"parent":{"ID":"YOU_MUST_WRITE_HERE_NEXT_ID_C1"},"child":{"KID":"YOU_MUST_WRITE_HERE_NEXT_KID_C3"}}
    ]
FOR rel in data
    LET parentId = FIRST(
        FOR c IN C1
            FILTER c.GUID == rel.parent.ID
            LIMIT 1
            RETURN c._id
    )
    LET childId = FIRST(
        FOR c IN C3
            FILTER c.GUID == rel.child.KID
            LIMIT 1
            RETURN c._id
    )
    FILTER parentId != null AND childId != null
    INSERT { _from: childId, _to: parentId } INTO C2
    RETURN NEW

希望对你有所帮助

其次 - 为什么在此片段中使用 С2 collection？

let exist = first(
    for c in C2

ArangoDB 插入边缘不存在

ArangoDB insert edge doesn't exists

arangodb