DynamoDB Tables Overview

5.4 Overview of DynamoDB Tables

This section explains all DynamoDB tables defined inside the backend architecture.
Each table serves a specific role in powering article management, user interactions, gallery rendering, location services, and user profiles.

Complete DynamoDB Tables Architecture

Full DynamoDB Tables

1. ArticlesTable

ArticlesTable Structure Purpose:
Stores all articles created by users. Each record represents a complete travel post including metadata, visibility settings, timestamps, and ownership.

Primary Key:

  • articleId (HASH)

Attributes:

  • visibility — public/private
  • createdAt — ISO timestamp
  • ownerId — ID of the user who created the article
  • status — draft/published/flagged

Indexes:

  • gsi_visibility_createdAt (visibility, createdAt) → For listing public articles in the home feed.
  • gsi_owner_createdAt (ownerId, createdAt) → For user profile pages.
  • gsi_status_createdAt (status, createdAt) → For admin filtering and moderation.

2. UserFavoritesTable

UserFavoritesTable Structure

Purpose:
Stores the relationship between a user and the articles they have favorited.

Primary Key (Composite):

  • userId (HASH)
  • articleId (RANGE)

This structure allows efficient:

  • Checking whether a user has favorited an article
  • Listing all favorites of the current user

3. GalleryPhotosTable

GalleryPhotosTable Structure

Purpose:
Stores metadata for individual images extracted from articles.
Used for gallery browsing, filtering by tags, and building trending metrics.

Primary Key:

  • photo_id (HASH)

Metadata may include:

  • articleId — which article the photo belongs to
  • S3 image key
  • detected tags
  • geolocation or timestamps

4. GalleryTrendsTable

GalleryTrendsTable Structure

Purpose:
Maintains tag popularity statistics for the gallery.
The article/image ingestion process updates counts within this table.

Primary Key:

  • tag_name (HASH)

Usage:

  • Provides trending tags for the homepage
  • Enables tag-based article recommendation

5. UserProfilesTable

UserProfilesTable Structure

Purpose:
Stores public profile information of users displayed in article feeds and profile pages.

Primary Key:

  • userId (HASH)

Attributes include:

  • avatar image URL
  • full name
  • bio/description

This table keeps profile data separate from Cognito, allowing customization and public display without exposing private identity data.

6. LocationCacheTable

LocationCacheTable Structure

Purpose:
Caches results from AWS Location Service’s reverse-geocoding to reduce cost and improve performance.

Primary Key:

  • geohash (HASH)

Attributes:

  • human-readable location
  • TTL — automatically deletes outdated entries

Summary

Together, these DynamoDB tables form the storage foundation for:

  • Article CRUD
  • Favorites
  • Gallery features
  • User profile rendering
  • Location lookup optimization

They are optimized for serverless workloads with high scalability and low latency.