title: GraphQL: Updating an array
body: <p>I'm having some issues updating an array in the resolver. I'm building with <code>typescript</code>.</p>
  
  <h2>Description</h2>
  
  <p>I have in the <code>datamodel.graphql</code> for <code>Prisma</code>:</p>
  
  <pre><code>type Service @model {
      id: ID! @unique
      title: String
      content: String
      createdAt: DateTime!
      updatedAt: DateTime!
      comments: [Comment!]! // Line to be seen here
      author: User!
      offer: Offer
      isPublished: Boolean! @default(value: "false")
      type: [ServiceType!]!
  }
  
  type Comment @model {
      id: ID! @unique
      author: User! @relation(name: "WRITER")
      service: Service!
      message: String!
  }
  </code></pre>
  
  <p>The <code>Prisma</code> is connected to the <code>GraphQl</code> server and in this one, I defined the mutation :</p>
  
  <pre><code>commentService(id: String!, comment: String!): Service!
  </code></pre>
  
  <p>So comes the time for implementing the resolver for the given mutation and I'm doing this :</p>
  
  <pre><code>async commentService(parent, {id, comment}, ctx: Context, info) {
      const userId = getUserId(ctx);
      const service = await ctx.db.query.service({
          where: {id}
      });
      if (!service) {
          throw new Error(`Service not found or you're not the author`)
      }
  
      const userComment = await ctx.db.mutation.createComment({
          data: {
              message: comment,
              service: {
                  connect: {id}
              },
              author: {
                  connect: {id:userId}
              },
          }
      });
  
      return ctx.db.mutation.updateService({
          where: {id},
          data: {
              comments: {
                 connect: {id: userComment.id}
              }
          }
      })
  }
  </code></pre>
  
  <h2>The problem :</h2>
  
  <p>The only thing I'm receiving when querying the playground is <code>null</code> instead of the comment I've given.</p>
  
  <p>Thanks for reading till so far.</p>