关系式连接和分页常见问题问答

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type Query {
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  viewer: User
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}
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type User {
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  id: ID!
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  posts(first: Int, after: String, last: Int, before: String): PostConnection!
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}
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"""
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This wrapper type contains the list of "edges" and
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pagination metadata.
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"""
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type PostConnection {
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  edges: [PostEdge!]!
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  pageInfo: PageInfo!
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}
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"""
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The "edge" wrapper contains metadata about the item in the
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list. By default it's just a cursor indicating the position
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of the item in the list, but additional metadata is allowed.
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"""
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type PostEdge {
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  """
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  The "node" is the actual item in the list.
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  """
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  node: Post
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  cursor: String!
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}
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type Post {
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  id: ID!
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  title: String
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  content: String
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}
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"""
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The specification includes the pagination metadata
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in a common type.
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"""
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type PageInfo {
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  hasNextPage: Boolean!
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  hasPreviousPage: Boolean!
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  startCursor: String
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  endCursor: String
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}

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query MyPosts($cursor: String) {
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  viewer {
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    posts(first: 5, after: $cursor) {
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      edges {
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        node {
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          id
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          title
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          content
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        }
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        cursor
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      }
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      pageInfo {
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        hasNextPage
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        endCursor
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      }
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    }
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  }
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}

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type Query {
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  viewer: User
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}
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type User {
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  id: ID!
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  posts(first: Int, after: String): PostConnection!
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}
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type PostConnection {
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  edges: [PostEdge!]!
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  pageInfo: PageInfo!
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}
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type PostEdge {
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  node: Post
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  cursor: String!
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}
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type Post {
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  id: ID!
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  title: String
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  content: String
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}
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type PageInfo {
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  hasNextPage: Boolean!
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  endCursor: String
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}

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query MyPosts($cursor: String) {
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  viewer {
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    posts(first: 5, after: $cursor) {
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      nodes {
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        id
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        title
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        content
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      }
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      pageInfo {
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        hasNextPage
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        endCursor
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      }
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    }
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  }
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}

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type Query {
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  viewer: User
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}
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type User {
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  id: ID!
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  posts(first: Int, after: String, last: Int, before: String): PostConnection!
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}
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type PostConnection {
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  nodes: [Post!]!
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  pageInfo: PageInfo!
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}
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type Post {
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  id: ID!
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  title: String
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  content: String
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}
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type PageInfo {
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  hasNextPage: Boolean!
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  hasPreviousPage: Boolean!
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  startCursor: String
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  endCursor: String
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}

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query MyPosts($page: Int) {
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  viewer {
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    posts(page: $page) {
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      nodes {
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        id
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        title
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        content
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      }
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      totalPages
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    }
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  }
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}

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type Query {
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  viewer: User
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}
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type User {
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  id: ID!
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  posts(page: Int): PostsPaginated!
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}
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"""
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This wrapper type uses a different suffix to distinguish
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it from Relay-style connection wrappers.
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"""
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type PostsPaginated {
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  """
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  Using `nodes` avoids the redundant
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  `{ posts { posts { id } } }` selection set.
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  """
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  nodes: [Post!]!
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  """
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  Adding pagination metadata directly to the
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  wrapper type works well.
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  """
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  totalPages: Int!
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}
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type Post {
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  id: ID!
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  title: String
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  content: String
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}