Best Shard Key Strategy for Multi-Tenant E-Commerce Platform

Hello everyone,

I have a large platform that provides eCommerce stores for people, similar to Shopify, and I’m facing a problem about choosing the best shard key for my collections.

Context:

1. Platform Overview:

• The platform allows users to create and manage their own online stores.
• We have multiple collections, such as orders, products, customers, etc.
• Each collection includes a store_id field to identify the store to which the document belongs.

2. Current Considerations:

• We are considering using store_id as the shard key for our collections to ensure that all documents related to the same store are located on the same shard.
• We aim to achieve data locality, reduce network overhead, and simplify querying across collections related to the same store.

3. Questions:

• Is using store_id as the shard key a good approach for our scenario?
• What are the potential pitfalls of using store_id as a shard key?
• Are there better alternatives or additional strategies we should consider to ensure optimal performance and scalability?
• How do we handle cases where certain stores have significantly more data than others, potentially causing unbalanced shards?
• What are the pros and cons of using a hashed shard key versus a ranged shard key for store_id in this context?
• Any best practices for sharding in a multi-tenant eCommerce platform would be highly appreciated.