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When implementing pagination in MongoDB, an important consideration is how to efficiently retrieve both paginated data and the total count of records. A common question developers face is whether to fetch the total count within the same aggregation function or as a separate query. In this article, we will explore two different approaches —  using a single aggregation pipeline with $facet , and separating count and data retrieval into distinct queries. We'll discuss their advantages, disadvantages, and when to use each approach for optimal performance. Approach 1: Single Aggregation Pipeline Using  $facet MongoDB’s $facet stage allows you to process multiple aggregation pipelines in a single query. This means you can get both the paginated data and the total count simultaneously. Example Aggregation with  $facet : const aggregateWithTotalCount = ( filters, sortField, sortOrder, page, pageSize ) => { return [ { $match : filters, }, { $facet : { ...

 Losing weight can be a challenging journey, but cardio exercise is one of the most effective ways to shed unwanted pounds and improve overall health. However, not all cardio workouts are created equal, and understanding what works best for weight loss can make all the difference. In this guide, we’ll explore the most effective cardio exercises, common mistakes to avoid, and how to maximize your results for sustainable fat loss. Why Cardio is Essential for Weight Loss Cardiovascular exercise, often called "cardio," refers to any physical activity that raises your heart rate and increases calorie burn. It helps create a caloric deficit , which is essential for weight loss. Some key benefits of cardio include: Burns calories effectively Improves heart health and endurance Boosts metabolism Enhances mental well-being Supports long-term fat loss when combined with proper nutrition Best Cardio Exercises for Weight Loss Not all cardio workouts yield the same results when it comes t...

  DeepSeek, a Chinese AI startup, has recently made headlines with the release of its latest model, DeepSeek-R1. This model has garnered significant attention for its innovative approach and impressive performance in the field of artificial intelligence. Background on DeepSeek Founded in 2023, DeepSeek emerged from the hedge fund High-Flyer, led by Liang Wenfeng. Initially focusing on AI-driven trading algorithms, the company transitioned to broader AI research, culminating in the establishment of DeepSeek as an independent entity. This shift allowed the company to concentrate on developing advanced AI models beyond financial applications. The DeepSeek-R1 Model DeepSeek-R1 represents a significant advancement in AI model development. Unlike traditional models that rely heavily on supervised fine-tuning, DeepSeek-R1 employs large-scale reinforcement learning (RL) as its primary training method. This approach enables the model to develop reasoning capabilities without extensive human...

When working with MongoDB and NestJS, ensuring the uniqueness of data fields can be challenging, especially when dealing with conditional constraints. A common requirement is to enforce unique email addresses only when the user account is active. This cannot be achieved directly using Mongoose’s unique: true constraint but can be handled effectively through several approaches. Solution 1: Using a Pre-Save Hook The pre-save hook allows checking for existing active email addresses before saving a new document. Here’s how you can modify your schema: import { Prop , Schema , SchemaFactory } from '@nestjs/mongoose' ; import mongoose, { Document } from 'mongoose' ; @Schema () export class User extends Document { @Prop ({ required : true }) fullName : string ; @Prop ({ required : true , maxlength : 50 }) email : string ; @Prop ({ required : true }) password : string ; @Prop ({ required : true , enum : [ 'active' , 'inactive' ], defa...

 Red Dye No. 3, also known as erythrosine, is a synthetic cherry-pink food coloring commonly used in various food products, beverages, and ingested medications. Its vibrant hue has made it a popular choice for items like candies, baked goods, and certain pharmaceuticals. Health Concerns and Regulatory Actions In the 1980s, studies indicated that high doses of Red Dye No. 3 could cause thyroid cancer in male lab rats. These findings led the U.S. Food and Drug Administration (FDA) to ban its use in cosmetics and topical medications in 1990. However, its use in food and ingested drugs continued. Over the years, consumer advocacy groups have raised concerns about the potential health risks associated with Red Dye No. 3, including its links to cancer and behavioral issues in children, such as hyperactivity. In response to a 2022 petition by food safety and health advocates, the FDA has taken decisive action. On January 15, 2025, the FDA announced a ban on the use of Red Dye No. 3 in all...

If you’re looking for a gentle, effective sunscreen for your family, the Round Lab Baby Mild Sunscreen is a fantastic choice! Here's why I absolutely love this product: 1️⃣ Gentle Ingredients for All Ages This sunscreen is formulated with mild ingredients that are perfect for sensitive skin. From babies to adults, it’s suitable for the whole family. I felt completely reassured using it on delicate skin, as it didn’t cause any irritation. 2️⃣ Smooth, Moisturizing Application One of the standout features of this sunscreen is its light, non-sticky texture. It glides effortlessly onto the skin, leaving it feeling hydrated and fresh without any greasiness. 3️⃣ Natural Finish Unlike many sunscreens, this one doesn’t leave a noticeable white cast. After application, my skin looked natural and clean, which makes it ideal for days when I skip makeup but still want sun protection. 4️⃣ Reliable Sun Protection With an adequate SPF and PA rating, this sunscreen provides solid prote...

If you encounter an error indicating that NestJS cannot resolve a Model in a service, it’s likely due to a missing injection setup. In the service constructor, you may be attempting to inject multiple models, but one or more models might not be correctly registered or injected. Let’s walk through the issue and how to resolve it. Problem Overview: In your module, you may have registered several models, but a model might be missing from the service’s constructor injection, leading to a runtime error. Solution: Add @InjectModel() Decorator To properly inject the model, ensure you use the @InjectModel() decorator in the service constructor. Updated Code Example: generic.service.ts import { Injectable } from '@nestjs/common'; import { InjectModel } from '@nestjs/mongoose'; import { Model } from 'mongoose'; import { GenericEntity } from './schemas/generic-entity.schema'; import { AnotherEntity } from './schemas/another-entity.schema'; @I...

  When using input fields like TextArea on iOS devices, you may notice that the screen automatically zooms when users tap on the field. This can disrupt the user experience. Below are some strategies to prevent this auto-zooming behavior. 1. Set the Font Size to At Least  16px iOS automatically zooms in on input fields when their font size is less than 16px . To prevent this, set the font size to 16px or more. Updated TextArea  Style: < Form . Item label={ < LabelField value = "Comments (Optional)" /> } name= "requestMemo" > < TextArea style = {{ fontSize: 16 }} // Prevents zoom on iOS placeholder = "Your comments will be sent to the driver." autoSize = {{ minRows: 2 , maxRows: 6 }} /> </ Form . Item > Setting fontSize: 16 ensures that the input field doesn’t trigger zooming when tapped. 2. Use viewport Meta Tag (For WebView or Mobile Browser) In mobile browsers or WebView applications, ensure the vi...

  When using Ant Design’s Modal , you might encounter situations where you need to trigger the form's submission through the modal's onOk button rather than the form's submit button. This can be achieved by programmatically calling the form's submit() method. Here's a detailed guide on how to do this. Scenario Overview: Suppose you want the form to be submitted only after the user confirms the action in the modal by clicking the OK button, instead of directly submitting via a form button labeled Submit Request . Solution: Use form.submit() in the Modal onOk  Handler To trigger the form’s submission programmatically, follow these steps: Move the submission logic into the onFinish function. Remove the htmlType="submit" from the form's main button to prevent auto-submission. Call form.submit() inside the modal's onOk handler to submit the form programmatically. Simplified Code Example: import React , { useState } from 'react' ; impor...

In Mongoose, a popular ODM (Object Data Modeling) library for MongoDB, using Number as a data type in your schema corresponds to the double type in MongoDB. Let’s explore what this means and how it impacts your data storage and retrieval. Number in Mongoose and double in MongoDB 1. Mongoose Type:  Number In JavaScript/TypeScript , Number is the primary floating-point type. When you specify Number in a Mongoose schema, MongoDB internally stores it as a double , which is a 64-bit floating-point value. This means that when you define a Number field in your Mongoose model, the corresponding MongoDB document will use the double type for that field. MongoDB Representation: When a Number field is saved in Mongoose, MongoDB represents it as: { "actualCollectionKg" : 12.34 // Internally stored as "double" in MongoDB } When running queries in MongoDB (e.g., using db.collection.find() ), you may see the following representation: "actualCollectionKg" :...