Hey, thanks for reading and for your question.
AlloyDB is in the "middle". It's when you want to serve a large (the exact size need to be defined) volume of transactional data at low latency AND to perform Analytics on this same data volume.
The promise is to remove the existing bottleneck that you can have with a legacy PostgreSQL confguration, and scale horizontaly the storage (to remove the IO bottleneck).
because of that, AlloyDB is a super charged PostgreSQL database! But there are still limits!
It's not a BigQuery like. I'm sure you can perform awesome things with a few dozens of Tb, maybe hundreds.
But, above the Tb, nothing can replace the power of BigQuery.
That's why, the "large volume of data" must be determined, and the way that you will query the data will also determine if it's the best solution for you or not. It's pretty new, too few feedbacks on that solution to advice more sharply.
