Aneesha S

Aneesha S

Error Testing Smart Contract in Solidity Ethereum

Error Testing Smart Contracts Featured Image

In this tutorial, I will teach you how to perform error testing for your smart contract in Solidity. Error testing is a crucial aspect of development especially when it comes to blockchain development. Unlike development using other technologies, blockchain technology…

findOneAndUpdate() and findAndModify() in MongoDB

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A MongoDB database has multiple collections. These collections can store millions of documents(data in MongoDB is called a document). MongoDB has various methods to fetch the documents from a collection such as find(), findOne(), findOneAndUpdate(), etc. We already have covered…

$and Operator in MongoDB – A Complete Guide

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In this tutorial, I will cover the $and operator in MongoDB. So, the $and operator performs an AND operation on the given array of expressions. It eventually selects ALL the documents that matched the query. This guide aims to provide…

Using the getIndexes() Function in MongoDB

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In this guide, I will explain how to use the getIndexes() Function in MongoDB. A list of documents describing the existing indexes in the collection includes hidden indexes, and is returned as an array by the getIndexes() function. This guide…

$all Operator in MongoDB – Simple Guide

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In this piece, I will discuss the $all operator in MongoDB. The $all operator identifies documents whose field value is an array containing all of the specified elements. It is more or less similar to the $and operator. This guide…

MongoDB Aggregation Size – Basic 2021 Guide

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In this guide, I am going to cover the MongoDB aggregation size operator. The aggregation size operator simply counts and returns the number of elements in an array. The aggregation size operator may accept any expression as long as it…