![]() ![]() It should be able to create, read, update, and delete resources. When building an API, you want your model to provide four basic functionalities. REST systems are stateless, scalable, cacheable, and have a uniform interface. Therefore, a RESTful API is an API that conforms to the REST architectural style and constraints. An API is an interface that software programs use to communicate with each other. Representational State Transfer (REST) defines a set of standards for web services. Let’s get started! What is a RESTful API? The complete code for the tutorial is available on this GitHub repo. ![]() ![]() Basic knowledge of working with the command line.Familiarity with the JavaScript syntax and fundamentals.To follow along with this tutorial, you‘ll need: Setting up CRUD functions in a REST API.Connecting to a Postgres database from Node.js.To do so, we’ll set up a route for each endpoint and a function for each query. Our goal is to allow CRUD operations, GET, POST, PUT, and DELETE, on the API, which will run the corresponding database commands. You’ll also learn how to install PostgreSQL and work with it through the command-line interface. Our API will be able to handle the HTTP request methods that correspond to the PostgreSQL database from which the API gets its data. We’ll also walk through connecting an Express server with PostgreSQL using node-postgres. In this tutorial, we’ll learn how to create a CRUD RESTful API in a Node.js environment that runs on an Express server and uses a PostgreSQL database. CRUD REST API with Node.js, Express, and PostgreSQLĮditor’s note: This post was updated on 06 June 2022 to reflect updates to the pgAdmin client.įor a modern web developer, knowing how to work with APIs to facilitate communication between software systems is paramount. The latter is an embedded JSON.Tania Rascia Follow Software developer, writer, maker of things. The sample program below retrieves a list of ‘customer_name’ and then a list of ‘description’ of ‘items’ of the sale. PreparedStatement ps = conn.prepareStatement(sql) įor (int i=0 i’ operator to retrieve values of the various keys in a JSON object. String sql = "INSERT INTO sales VALUES (?, ?::JSON)" The simple Java program below inserts 4 records into the table we just created. The JSON data type checks for a valid JSON format, so insert statements should be mindful of that. ![]() We create a table ‘sales’ below (which we will use in subsequent examples) containing 2 columns, ‘id’ and ‘sale’, with the latter being a JSON: json_sample=# CREATE TABLE sales (id INT, sale JSON) Re-parsing is not needed, making data processing significantly fasterĪll white space and line feeds in the input are preserved as-isĮxtra white space and line feeds are strippedĭuplicate keys are retained, processing functions only consider the last valueĭuplicate keys are purged at input, only the last value is storedĪ JSON column is created just like any other data type. Processing functions must re-parse the data on each execution Input is slightly slower, as there is an overhead related to binary conversion Input is fast, as no conversion are required Major differences between JSON & JSONB are highlighted in the table below: JSONB was introduced as a native data type in v9.4 of PostgreSQL and it stores JSON objects in binary format. String manipulation and parsing are very expensive operations in a database, so although you could have potentially stored JSON objects in strings in PostgreSQL before, introduction of the native data type has taken away overheads and made throughput a lot faster for JSON manipulation. Subsequent releases introduced JSONB (binary formatted JSON objects) and many data manipulation functions for JSONs, making it a very powerful tool for NoSQL operations. Starting v9.2, PostgreSQL is providing native data type support for JSON objects. For links to other blogs in this series, please scroll to the end of this post. This is part of a series of blogs on Java & PostgreSQL. PostgreSQL 9 Cookbook – Chinese Edition.PostgreSQL Server Programming Cookbook – 2nd Edition.PostgreSQL 9 Administration Cookbook – 3rd Edition.PostgreSQL High Availability Cookbook – 2nd Edition. ![]()
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