Import single json creating unique nodes and edges

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1

Hi, I want through the tutorial, I have no problem loading json data, however, I don’t know how to load json data from a single file while creating unique nodes and edges.

Using this dataset as example: SNAP: Network datasets: Wikipedia vote network

This file has 7115 nodes and 103689 edges. The data structure is:

FromNodeId ToNodeId
30 1412

How we interpret is that Node 30 votes for Node 1412.

After doing data transformation, my json file data structure is:

[
 {"FromNodeId": 30, "ToNodeId": 1412},
 ...
]

I import the file using ./dgraph live -f wiki-vote.json. This will create 103689 nodes containing both FromNodeId and ToNodeId attributes and each has unique uid.

What I want is to create unique nodes from FromNodeId and ToNodeId. With edges votes_for from FromNodeId to ToNodeId.

My attempt is to rename both FromNodeId and ToNodeId to uid, the idea is to ensure that I only have 7115 uid from 7115 unique nodes from both columns, which don’t work. Also I have no idea how can I define the relationship of FromNodeId and ToNodeId inside the json file.

[
 {"uid": 30, "uid": 1412},
 ...
]

Please advise how can I do that :slight_smile:

2

The correct JSON syntax for Dgraph would be

[ 
 { 
    "uid": "_:30", 
    "ToNodeId": [ { "uid": "_:1412" } ] 
 },
 ...
]

Note that you have to add the prefix _: in order to make them “unique” via blank node. Remember that Blank Nodes guarantees the uniqueness only in the procedure context(or transaction context) you can’t use it for future insertions/mutations.

It may possible to use numbers or hex, but you have to lease several uids from zero before doing it.

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