Firebase Destination

Cloud Firestore is a flexible, scalable database for mobile, web, and server development from Firebase and Google Cloud. Like Firebase Realtime Database, it keeps your data in sync across client apps through realtime listeners and offers offline support for mobile and web so you can build responsive apps that work regardless of network latency or Internet connectivity. Cloud Firestore also offers seamless integration with other Firebase and Google Cloud products, including Cloud Functions.
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The different types of destinations

There is no one size fits all solution when it comes to databases, datalakes and data warehouses. Each one had different benefits and drawbacks which you can read more about here

Analytical vs Transactional

Analytical Data Stores (OLAPs)

The analytical data stores include normally all of the data warehouse vendors such as Snowflake, Redshift, Bigquery and many others. Analytical data stores are normally columnar data bases which are optimized for storing vast amounts of data at a decent price while at the same time allowing you to issue complex queries to understand your business data.
Using one of this solutions for operational queries where a lot of updating happens would be costly and inefficient.

Transactional Data Stores

Transactional Data Stores are more commonly used for operational workloads such as managing all the data from a web application. Common web solutions such as Wordpress rely on these type of data stores. Some examples are MongoDB, Postgresql, MySQL and many others.
These type of data bases can handle a huge volume of updates as users interact with the product.