The danger of not using ORM (object-relational mapping) / ODM (object-document mapping) is that every time you make changes to the structure of the data, you have to modify the application code. Do you need a better explanation of how to use Node.js with MongoDB? The most popular choice is the Mongoose library. NodeJS (JavaScript on the server) is awesome, but some developers are confused about NoSQL when it comes to working in Node with MongoDB (NoSQL database). This is especially true for new and emerging technologies like NodeJS. And it’s not our fault, because in most cases there are just no good tutorials. If you are seeing this page, then you are somewhat related to software engineering, and we all know that for people in tech learning a new technology is important. Thankfully, Mongoose.js makes it painless to use comparison operators like greater than ($gt), greater than or equal to ($gte), less than ($lt), and less than or equal to ($lte).Īdd these two functions to query.js and make sure to comment out the function call to findUserByFirstName.Mongoose Course: Node and Mongo Explained Let’s say you need to find all the users who are older than 50. Use findOne() when you only need to get one document from your database.find() With Comparison Operators

Note: find() always returns an array of documents. Once you run index.js again, you should see Luke’s document logged in the terminal! Then, call findUserByFirstName with “Luke” as an argument. Make sure to comment out the findAllUsers. This code, when run, will return the user whose’s firstName is equal to “Luke.”.This object must contain at least one key and value to specify the condition you want the returned data to meet. find() can optionally take in an object as a parameter.

This code creates another async function, but this time, it takes in an argument.

Add this snippet after the findAllUsers function.

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