What is difference between Mutation and Query?

In GraphQL, both “Mutation” and “Query” are root-level operation types that define the entry points for interacting with the server. However, they serve different purposes:

  1. Query: The “Query” type is used for reading data from the server. It represents the root level of data access for GraphQL queries. When a client wants to fetch data from the server, it formulates a query, specifying the fields it wants to retrieve, and sends it to the GraphQL server.Queries are read-only operations, meaning they should not cause any side effects on the server or modify data. They are used to retrieve data based on the provided arguments. In a GraphQL schema, the “Query” type consists of fields, and each field represents a different query that clients can execute.For example, in a social media application, a client might use a query like this to get information about a user based on their ID:
query {
  user(id: "123") {
    id
    name
    email
    posts {
      title
      content
    }
  }
}
  1. Mutation: The “Mutation” type is used for modifying data on the server. It represents the root level of data modification for GraphQL. When a client wants to create, update, or delete data on the server, it formulates a mutation and sends it to the GraphQL server.

Unlike queries, mutations can cause side effects on the server, and they are used to modify or create data. Like the “Query” type, the “Mutation” type also consists of fields, and each field represents a different mutation that clients can execute.

For example, a client might use a mutation like this to create a new user on the server:

mutation {
  createUser(name: "John Doe", email: "[email protected]") {
    id
    name
    email
  }
}

In summary, the key differences between “Mutation” and “Query” in GraphQL are:

  • “Query” is used for reading data (fetching) and is read-only.
  • “Mutation” is used for modifying data (creating, updating, deleting) and can cause side effects on the server.
  • Both “Mutation” and “Query” consist of fields that represent different operations that clients can execute, but their purpose and the types of operations they support are different.
error: Content is protected !!