Select distinct values / deduplicate

Users Dgraph
,
1

I have this data/nodes :

[
 {name: "Tom" , age: 42 },
 {name: "Jerry", age: 12 },
 {name: "Tom",  age: 35 }
]

I would like to run a DQL query that returns all unique names: ["Tom", "Jerry"]
how?

2

It looks like groupBy sort of does this, but it is not available in graphQL and only DQL. This basically means you need to do a @custom dql query. The problem is that you can’t use @auth on a custom query, so that only leaves putting a custom DQL within a custom mutation @lambda.

https://dgraph.io/docs/query-language/groupby/#

Hopefully this is a new feature request they plan on adding.

J

3

I have tried to use groupby, like this:

{
    people as var(func: has(dgraph.type, Person))
    nameCounts as var(func: uid(people) ) @groupby(name) { count(uid)}
    ...
}

(doesn’t work)
The problem is that you can’t assign this groupby to a variable, which I need to keep processing.
It does work if it is your final result

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