Description: A selection set is a collection of fields that a client requests in a GraphQL query. This feature allows developers to specify exactly what data they want to receive from the server, thus optimizing the amount of information transferred and improving the efficiency of applications. Unlike traditional REST APIs, where responses may include unnecessary data, in GraphQL the client has full control over the structure of the response. This translates into greater flexibility and customization, as developers can tailor queries to the specific needs of the application. Additionally, selection sets allow for nested queries, meaning related data can be requested in a single query, reducing the need for multiple server calls. This ability to precisely define the required data not only enhances performance but also facilitates code maintenance and the evolution of applications as data requirements change.
History: GraphQL was developed by Facebook in 2012 and was made public in 2015. The need for a system that allowed developers to obtain only the necessary data for their applications led to the creation of this technology. Since its release, GraphQL has evolved and has been adopted by many companies and development communities, becoming a standard for building efficient and flexible APIs.
Uses: Selection sets are primarily used in the development of web and mobile applications that require efficient communication with servers. They allow developers to optimize data queries, reducing the amount of data transferred and improving user experience. They are also useful in situations where hierarchical access to related data is needed.
Examples: A practical example of a selection set in GraphQL could be a query requesting a user’s name and age, as well as the titles of their posts. The query might look like this: `{ user { name age posts { title } } }`, allowing for the retrieval of only the necessary information without loading any unnecessary additional data.
