Question

我正在尝试对来自this answer的查询进行修改。我希望能够进一步过滤顶点，这样我就可以自定义前十名（让它成为特定年份中具有最多角色的十大演员或类似的东西）。

如果我尝试使用NEIGHBORS功能，我会收到以下错误：

arangosh [_system]> db._createStatement({query: 'FOR vert IN imdb_vertices FILTER vert.type == "Person" LET edge_count = (LENGTH(NEIGHBORS(imdb_vertices, imdb_edges, vert, "outbound", [{"type": "Role", "$label": "ACTS_IN"}]))) SORT edge_count DESC LIMIT 10 RETURN {"name": vert.name,  "count": edge_count}'}).execute().toArray()
JavaScript exception in file '/usr/share/arangodb/js/client/modules/org/arangodb/arangosh.js' at 101,13: TypeError: TypeError: Object #<ShapedJson> has no method 'indexOf'
!      throw new TypeError(requestResult.errorMessage);
!            ^
stacktrace: TypeError: TypeError: Object #<ShapedJson> has no method 'indexOf'
    at Object.exports.checkRequestResult (/usr/share/arangodb/js/client/modules/org/arangodb/arangosh.js:101:13)
    at ArangoStatement.execute (/usr/share/arangodb/js/client/modules/org/arangodb/arango-statement.js:171:12)
    at (shell):1:290

由于NEIGHBORS似乎返回了边和顶点（与返回边的EDGES不同），我认为问题可能就是这样，所以我尝试使用路径：TRAVERSAL：false选项。不幸的是它给出了同样的错误：

db._createStatement({query: 'FOR vert IN imdb_vertices FILTER vert.type == "Person" LET edge_count = (LENGTH(TRAVERSAL(imdb_vertices,imdb_edges, vert, "outbound", {paths: false, followEdges: [{"type": "Role", "$label": "ACTS_IN"}]}))) SORT edge_count DESC LIMIT 10 RETURN {"name": vert.name,  "count": edge_count}'}).execute().toArray()
JavaScript exception in file '/usr/share/arangodb/js/client/modules/org/arangodb/arangosh.js' at 101,13: TypeError: TypeError: Object #<ShapedJson> has no method 'indexOf'
!      throw new TypeError(requestResult.errorMessage);
!            ^
stacktrace: TypeError: TypeError: Object #<ShapedJson> has no method 'indexOf'
    at Object.exports.checkRequestResult (/usr/share/arangodb/js/client/modules/org/arangodb/arangosh.js:101:13)
    at ArangoStatement.execute (/usr/share/arangodb/js/client/modules/org/arangodb/arango-statement.js:171:12)
    at (shell):1:318

有人可以解释我收到此错误的原因吗？

Answer 1

我认为问题是上面查询中的 vert 是一个顶点对象，但它应该是一个顶点_id（或顶点_key）。这就是发生异常的原因。

第一个查询可以修改如下：

db._createStatement({query: 'FOR vert IN imdb_vertices FILTER vert.type == "Person" LET edge_count = (LENGTH(NEIGHBORS(imdb_vertices, imdb_edges, vert._id, "outbound", [{"type": "Role", "$label": "ACTS_IN"}]))) SORT edge_count DESC LIMIT 10 RETURN {"name": vert.name,  "count": edge_count}'}).execute().toArray()

TypeError：Object＃<shapedjson>没有方法＆＃39; indexOf＆＃39; </shapedjson>

1 个答案: