Delve into building a GraphQL endpoint with Deno, compare technologies, configure queries, and integrate PostgresSQL and MongoDB databases to create a secure, high-performing application.

deno.tar.gz

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Deno is a modern and secure runtime for JavaScript. It was created by the same team that created Node.js. Deno offers better performance, security, and simplicity than any other JavaScript runtime.

In this course, you will start by understanding the different technologies used in Deno, such as Typescript. You will compare these technologies with JavaScript and GraphQL as well as learn their terminologies. Then, you will create your own endpoint with Deno and configure queries and mutations in it. Next, you will explore two different databases with Deno: first, you’ll learn how to set up an SQL database using PostgresSQL and then how to configure a NoSQL database using MongoDB to store documents and collections of on-demand data. Finally, you’ll put everything together to have a fully functioning GraphQL endpoint made with Deno and backed by PostgreSQL and MongoDB. 

After this course, you’ll be able to create a Deno application and a GraphQL endpoint while having a database of your choice to store data.

Building a GraphQL Endpoint with Deno

At its core, GraphQL relies heavily on two simple keywords: query and mutation. We’ll explore these concepts in detail in this lesson.

> **Note:** You can use the code widget at the end of this lesson to run the queries and mutations.


# Queries in GraphQL

As its name suggests, a **query** is what the client prepares to request data from the server. Unlike REST, GraphQL exposes one API, so a query is needed to specify what’s needed from the server. For example, if we want to fetch courses by their titles, we can send the following query:

Learn about the basic concepts of GraphQL.

Introduction to Deno, TypeScript, and GraphQL

Creating a Basic GraphQL Endpoint

Databases and Deno

SQL: Postgres and Deno

NoSQL: Mongo and Deno

Wrapping Up

Appendix

Basics of GraphQL

Queries in GraphQL