DEV Community: Anuj Pancholi

Answer: How to efficiently export 3 million documents from MongoDB Atlas collection to CSV file using NodeJS?

Anuj Pancholi — Thu, 20 Jan 2022 06:36:44 +0000

answer re: How to efficiently export 3 million documents from MongoDB Atlas collection to CSV file using NodeJS

Jan 19 '22

I personally would NEVER recommend using .toArray() to query an indefinite/very large no. of documents, as you're asking nodejs to fetch 3milllion documents from your db and store the whole thing in one humongosaurus array in memory. Hope you have a high-spec computer. Also, it won't write anything to a…

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Simple Implementation of Builder Pattern in JS.

Anuj Pancholi — Sat, 15 Jan 2022 11:18:09 +0000

answer re: Mongodb find method can take dynamic query?

Jan 15 '22

The general problem you're facing here is the problem of building complex objects based on some parameters/inputs, which can be solved via a design pattern known as the builder pattern.

Though implementing such patterns can make your code look a bit complex (take this for example), here's my very simple…

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Logging Axios Request and Response Headers

Anuj Pancholi — Sat, 15 Jan 2022 07:34:30 +0000

Jan 14 '22

Here's what I usually do:

In the request interceptor, I use some UUID library (or maybe the crypto core module of node) to generate a UUID, then attach it to the config object as a request ID, say config.reqId. Same config object should be accessible in response.config, or…

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Answer: How to pull a pot of gold out of a deeply nested object in js.

Anuj Pancholi — Sat, 10 Oct 2020 07:20:45 +0000

answer re: How do I combine keys from an array of elements and assign it to an object?

Oct 10 '20

From what I understand, the object that you have is a deeply nested object and the array you have describes a path in that nesting. So, this method will return some result if it finds it, given the array of keys and the object (if there is indeed some "pot…

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A "Nested Grouping" of sorts In MongoDb

Anuj Pancholi — Sat, 19 Sep 2020 08:39:42 +0000

answer re: Grouping objects inside an array - MongoDB Aggregation

Sep 19 '20

Mongo Playground Link

I think this is the precise format you wanted.

The aggregation pipeline:

[
  {
    "$unwind": {
      "path": "$scores"
    }
  }
  {
    "$match": {
      "scores.type": "homework"
    }
  },
  {
    "$group": {
      "_id": {
        "class_id": "$class_id",
        "student_id": "$student_id"
      },
      "scores": {
        "$push": {
          "type": "$scores.type",
          "score": "$scores.score"
        }
      }

…

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Answer: Deleting Multer uploads object after processing Express

Anuj Pancholi — Sat, 12 Sep 2020 08:56:39 +0000

answer re: Deleting Multer uploads object after processing Express

Sep 11 '20

The createReadStream function in fs also may take a buffer as an input, however, it seems that fs.createReadStream() converts that buffer to a string which ultimately must contain a file path (which seems like an important detail they should've mentioned in the docs).

Multer has a feature where instead of…

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Answer: is there any query to find documents by checking a field of a nested embedded document in mongoDb

Anuj Pancholi — Thu, 27 Feb 2020 16:23:40 +0000

answer re: is there any query to find documents by checking a field of a nested embedded document in mongoDb

Feb 27 '20

Disclaimer: I have not used Mongoose yet, but in the comments you said that a mongodb query will also be helpful.

Based on the Mongoose schemas you have described, I mocked 10 documents for products and 3 for invoices using Mockeroo (https://mockaroo.com/). Note that the objectIds are…

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Answer: How to pass variables in URL in NodeJS

Anuj Pancholi — Tue, 25 Feb 2020 16:09:23 +0000

answer re: How to pass variables in URL in NodeJS

Feb 25 '20

One way to do it is using template literals, which has been discussed in other answers (I encourage you to check out the link shared by Jason).

const phone = "1234567890";
const message = "my-message-content";

const url = `http://www.techsolver.in/http-api.php?username=abc&password=pwd&senderid=MYID&route=1&number=${phone}&message=${message}`

console.log(url);

However, if…

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Why node has a querystring module, to perform tasks that, at first glance, seem trivial.

Answer: How I should save the relational data in mongoose?

Anuj Pancholi — Mon, 24 Feb 2020 17:21:26 +0000

answer re: How I should save the relational data in mongoose?

Feb 24 '20

I'd like to start off by saying that if your project is using relational data, I highly recommend that you use a relational database instead of MongoDb. I love Mongodb as much as the next guy, and have done projects in Mongodb using relational data, but I've faced problems…

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A bit about modelling some relational data in mongodb involving restaurants and their reviews.