如何在JanusGraph或Gremlin中“連接”頂點及其邊數作為這些頂點的“屬性”？

Question

我需要返回“帖子”頂點，但是那些帖子具有一些“喜歡”邊緣，我如何返回該帖子的“喜歡”邊緣的計數作為該邊緣的屬性，如下所示：

{標題：“ lorem ipsum .....”，內容：“ yadayadayada”， 喜歡 ：6 <----}

Answer 1

以TinkerPop的現代玩具圖為例，您可以執行以下操作：

gremlin> g.V().as('a').
......1>   map(outE('created').count()).as('count').
......2>   select('a','count').by(valueMap()).by()
==>[a:[name:[marko],age:[29]],count:1]
==>[a:[name:[vadas],age:[27]],count:0]
==>[a:[name:[lop],lang:[java]],count:0]
==>[a:[name:[josh],age:[32]],count:2]
==>[a:[name:[ripple],lang:[java]],count:0]
==>[a:[name:[peter],age:[35]],count:1]

它以“ a”返回頂點的屬性，並以“創建的”邊數計數。 您可能還選擇使用project() ：

gremlin> g.V().
......1>   project('a','knows','created').
......2>     by(valueMap()).
......3>     by(outE('knows').count()).
......4>     by(outE('created').count())
==>[a:[name:[marko],age:[29]],knows:2,created:1]
==>[a:[name:[vadas],age:[27]],knows:0,created:0]
==>[a:[name:[lop],lang:[java]],knows:0,created:0]
==>[a:[name:[josh],age:[32]],knows:0,created:2]
==>[a:[name:[ripple],lang:[java]],knows:0,created:0]
==>[a:[name:[peter],age:[35]],knows:0,created:1]