Regarding the avoidance of N+1 queries when using the combination of prismaConnection and t.relation

[touyu]

As shown in the code below, when prismaField is used in queryField and t.relation is used inside prismaObject, a query is issued that avoids the N+1 problem.

builder.prismaObject('Article', {
  fields: (t) => ({
    databaseId: t.exposeInt('databaseId'),
    creator: t.relation('creator', {
      nullable: true,
    }),
  }),
})

builder.queryField('articles', (t) =>
  t.prismaField({
    type: ['Article'],
    resolve: (query) => {
      return prisma.article.findMany({
        ...query,
      })
    },
  })
)

Next, As shown below, when prismaConnection is used in queryField and t.relation is used inside prismaNode, a large number of queries are issued.

In such a case, doesn't t.relation generate a query that avoids the N+1 problem?

builder.prismaNode('Article', {
  id: { field: 'databaseId' },
  fields: (t) => ({
    databaseId: t.exposeInt('databaseId'),
    creator: t.relation('creator', {
      nullable: true,
    }),
  }),
})

builder.queryField('articles', (t) =>
  t.prismaConnection({
    type: 'Article',
    cursor: 'databaseId',
    resolve: (query, parent, args) => {
      return prisma.article.findMany({
        ...query,
      })
    },
  })
)

[hayes]

I would expect that this would create one Prisma query, and which would result in 2 SQL queries. Do you have any more details to share on what's going on here? Wasn't able to reproduce the issue, and there are several tests covering similar patterns showing optimized queries

[touyu]

@hayes
Thanks for the reply.
I created a sample code that can be reproduced here.
Could you please check here?
https://github.com/touyu/pothos-prisma-query

README.md describes the query to reproduce.

[hayes]

@touyu are you using the jsonprotocol preview feature for prisma?

[hayes]

opened a couple PRs to prisma to hopefully get this fixed: prisma/prisma-engines#4014 and prisma/prisma#19554)

[touyu]

are you using the jsonprotocol preview feature for prisma?

I don't use jsonprotocol.

opened a couple PRs to prisma to hopefully get this fixed: prisma/prisma-engines#4014 and prisma/prisma#19554)

Great! I will keep watch on these PRs.
Thank you!

[hayes]

can you upgrade prisma and pothos/plugin-prisma to the latest versions and see if your issue is resolved? I pushed a fix for optimizing nodes last week, and prisma has released my fix for optimizing findUniqueOrThrow calls, so I think this should work as expected now

[touyu]

@hayes Thank you for the great job you do!