Well, you can't necessarily trust open source for business software.
The more deeply your business depends on something, the more careful you need to be when selecting the source for that something. (And the db is often very deeply depended on.)
You want to see why their long-term incentives align with your own needs.
But a revenue stream is just one way to do this, and not a perfect one. (Case in point: Oracle.)
In my experience, SQL Server isn't bad though. I know a couple commercial products that started with SQL Server in the late '90s and remain happy with it now. The cost hasn't been a problem and they like the support and evolution of the product. They find they can adopt newer versions and features when they need to without too much pain/cost/time.
(Not that I don't think Postgres is generally a better green-field pick, though, and even more so porting away from Oracle.)
The more deeply your business depends on something, the more careful you need to be when selecting the source for that something. (And the db is often very deeply depended on.)
You want to see why their long-term incentives align with your own needs.
But a revenue stream is just one way to do this, and not a perfect one. (Case in point: Oracle.)
In my experience, SQL Server isn't bad though. I know a couple commercial products that started with SQL Server in the late '90s and remain happy with it now. The cost hasn't been a problem and they like the support and evolution of the product. They find they can adopt newer versions and features when they need to without too much pain/cost/time.
(Not that I don't think Postgres is generally a better green-field pick, though, and even more so porting away from Oracle.)