Introduction: What is GraphQL?

GraphQL is a query language and runtime developed by Facebook to address the limitations and complexities of traditional REST APIs.

One of the main advantages of GraphQL is its flexibility and efficiency.

<aside> 💡 Unlike REST, which requires multiple endpoints for different resources and often returns more data than needed, GraphQL enables clients to request precisely the data they require, and nothing more, from a single endpoint.

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Benefits

You can tailor your queries to specify the exact fields and relationships required, reducing over-fetching and under-fetching of data.

Furthermore, GraphQL promotes strong typing and introspection. With its schema definition language, both the server and client can clearly understand the data's structure and types, facilitating better communication and documentation.

In addition, GraphQL:

Allows multiple queries to be combined into a single request, saving roundtrips to the server and reducing latency.
Enables real-time data retrieval through subscriptions, making it suitable for building real-time applications, like chat apps or live notifications, but this capability is not yet supported in Salesforce.
Allows for versionless APIs. By having a single evolving API schema, clients can adapt to changes incrementally without the need to create new versions, avoiding the complexities and maintenance overhead often associated with versioned REST APIs.

Current status of the GraphQL Salesforce flavor

Salesforce does not offer all the capabilities available on the GraphQL standard, but instead, limited to queries and even with some limitations.

Updating data, known as mutations and many other capabilities are not yet offered, this following table summarized the state of the art:

Feature	Salesforce GraphQL	GraphQL Standard
Subscriptions	No	Yes
Mutations	Beta	All objects
Scalar types	Limited set	Full set
Interfaces	No	Yes
Unions	No	Yes
Naming convention	Different	Same
Additional features	Field-level security	None

What does a query look like?

Queries in GraphQL language are JSON-like queries that are straightforward to understand coming from a SQL or SOQL background.

The following query retrieves all book records with the fields title, and author.


query {
  book {
    title
    author
  }
}