GraphQL mutation

As explained in Quarkus in Action

A GraphQL mutation is a GraphQL operation that can add or modify data and may return data with the update.

A GraphQL mutation is an operation for changing existing data or adding new data. Like an SQL UPDATE or INSERT, or a REST PUT or POST, it accepts parameters and can return data with the update. section 4.4

Mutations differ from read-only queries in several practical ways:

• Declare the operation with the mutation keyword. section 4.5.2
• Pass input arguments, such as a CarInput object containing the fields needed to create a car. section 4.5.2
• Select fields from the returned object; complex return types require an explicit field selection. section 4.5.2
• Return the stored object, including generated values such as an ID, when those fields are selected. section 4.5.2

Registering a car

A register mutation adds a Peugeot 406 to a fleet and requests the returned license plate, model, manufacturer, and ID. The response echoes those values and includes the generated ID 3. Running the cars query afterward verifies that the database contains the new car. section 4.5.2

Figure 4.3 GraphiQL is an HTML and JavaScript-based UI for manually executing GraphQL operations.

Use GraphiQL to enter, autocomplete, execute, and review GraphQL mutations through a browser-based interface. section 4.5.2

How Quarkus in Action covers it

How deep it goes

Defines operation semantics and demonstrates input, field selection, response echoing, and database verification without covering advanced GraphQL features.

Examples

Demonstrates a register mutation that creates a fleet car, echoes selected fields, and verifies persistence with a cars query.

What it assumes

Assumes familiarity with GraphQL fields and queries while introducing mutation syntax, input objects, and complex-result selection.

What you can do after

Apply it via GraphiQL by supplying mutation arguments, selecting response fields, executing the operation, and checking the resulting data.

How it connects

Relates mutations to GraphQL queries, SQL INSERT and UPDATE, REST POST and PUT, GraphiQL, and input object types.

liveBookmanning.com

Read Quarkus in Action on liveBook Get the book at manning.com

Also explained in

• 

  liveBookmanning.com
  Building Web APIs with ASP.NET CoreA GraphQL mutation is an operation that requests a state-changing action from a GraphQL server and can return selected resulting fields.

Compare how 2 books explain GraphQL mutation →

Related concepts

• BananaCakePopused by · Banana Cake Pop is a web-based GraphQL client and IDE for composing, executing, and inspecting GraphQL operations.
• GraphQL operationkind of · A GraphQL operation is an executable request that specifies a query, mutation, or other interaction with a GraphQL schema.
• request messageuses · An HTTP request is a message sent by a client to a server that specifies a method and target and may include headers and a body.
• SQLcontrasts with · SQL is a standardized declarative language for defining, querying, and manipulating data and structures in relational database systems.
• database management toolproduces · A database management system is software that defines, stores, retrieves, modifies, and administers database data and controls access to it.
• bearer authenticationconfigured by · Bearer authentication is an authentication scheme in which presenting a bearer token is sufficient to use the access or authorization granted by that token.

This explainer was generated by Manning's knowledge graph from the text of Quarkus in Action. The section links point to the parts of the book it draws on.