Node.js

MongoDB CRUD Operation with Node.js

Once you get your head around MongoDB CRUD operations with Mongo Shell, getting Node.js to do them becomes easy. If you are still not confident with MongoDB, check out MongoDB skills essentials exercise to brush up your MongoDB skills. We will create a collection called, students. Then, we will insert …

DBA

How to Prevent Creating Duplicate Keys in MongoDB

In MongoDB, the primary key is reserved for the _id field. This is a system field and gets created by default when inserting new records. When you want to enforce the uniqueness in other fields, you can use unique index. Here is how to create unique index with Mongo Shell. …

DBA

MongoDB Skills Essential Exercise

MongoDB is probably the most prevalent NoSQL database choice for the backend of web applications. It is an open source and relatively easy to use. It works well with the modern web applications written in Node.js or Python Django. Enterprise-level web application platforms like Sitecore (works on .NET) also use …

DBA

User Management with MongoDB

MongoDB does not have authentication out of box. When you install it, the first thing you have to do is to create an admin user in the admin database and enable authentication. After installation, you can get into MongoDB with the mongo command from the Mongo Shell. mongo Let’s create …

Data Engineering

REST API Data Ingestion with Node.js

The classic REST API data ingestion pattern is (1) to make an API call to the endpoint, (2) get the data, (3) transform it to a structured table and (4) load it to a database. Let’s have a go at it with Node.js. We are using JSONPlaceholder which offers a …

Data Engineering

Converting JSON to CSV and Loading it to Postgres with Node.js

To convert JSON to CSV, I love using json2csv. It really does all the hard work of working the JSON structure out and converting it to a flat file. For nested JSON elements, you can simply specify them by the dot notation (like transaction.itemId). When it contains an array element, …

Data Engineering

Converting CSV to JSON and Loading it to Postgres with Node.js

To convert csv to json, Node has an awesome module, csvtojson. It takes a json file and convert it to csv asynchronously. Once we convert csv to json, let’s load it to a Postgres table with jsonb data type. Postgres supports JSON data and you can query it (see the …

Data Engineering

Bulk Loading Postgres with Node.js

The fastest way to bulk load data into Postgres is to call Copy, which is a SQL command to load data into a table from a flat file. To connect to Postgres with Node.js, we can use the node-postgres module (pg). To use the copy function, we can use the …

Data Engineering

A Comprehensive Guide for Reading and Writing JSON with Python

A Comprehensive Guide for Reading and Writing JSON with Python The json module enables you to read JSON object from a file or HTTP response and write it to a file. It is worthwhile to spend a little bit of time to understand a few key functions that are often …

Data Engineering

Testing and Prototyping for REST API Data Ingestion with JSONPlaceholder

JSONPlaceholder is a web service that offers REST API endpoints for example JSON data. If you needs to experiment with REST API quickly, this is a really great tool that you can use. It supports all the HTTP verbs. As for testing and prototyping REST API data ingestion, you can …