[verbin217]

https://github.com/graphql/graphql-js

Just implement resolve.

[xtrumanx]

If you have two fields in a query, does that mean two resolve functions? If I using a SQL database and the two fields were stored on two columns on the same table, wouldn't that cause 2 SQL queries to be run?

[leebyron]

Only if each field required loading a new row, and even then batching can be used to turn this back into one query.

eg: { firstName, lastName } doesn't need to load new rows but { mother { name }, father { name } } does need to load new rows.

DataLoader (https://github.com/facebook/dataloader) is a small utility which makes batching and caching database requests straight forward.

[verbin217]

Yes. But only one http request. If they're both the same query but access a different field you might be able to cache it.

[devit]

Sangria in Scala has a mechanism called "Deferred" that lets you specify that it should ask you to resolve objects of a certain type all at once at the end, and you would do a single SQL query per object type there.

If the JavaScript implementation doesn't have something like this, perhaps it can be hacked on top.

[santialbo]

and you'll end up with an endpoint that can potentially bomb your datastore

    query User {
      friends {
        friends {
          friends {
            ...
          }
        }
      }
    }

how do you prevent something like this happening on graphQL backed with a series of resolves that query a SQL database?

[estefan]

Limit recursion with a max depth parameter (sangria)

[santialbo]

I don't need that many levels to make it explode and you probably don't want to set a very low max depth since it beats the purpose of graphql itself.