We use PostreSQL. We ran into the issue with Google Cloud SQL (PostreSQL-flavored) that we can not make it multi-region, only multi-zone. With Google Cloud SQL (MySQL-flavored) you can do multi-region.

I would feel much better if we had multi-region failover with PostreSQL just in case a Google Data Center region (which contains the multi-zones) goes completely down (as it did in early June 2019.)

We have some manual solutions to this, but I would have prefered one that just worked with Google Cloud SQL out of the box. I think I am not the only one in this situation with this problem.