What's the best relational database software for tech startups?

Exploring the best relational database options for tech startups. The ideal solution should offer scalability, ease of management, and affordability in the early stages.

Below are several tools frequently recommended on G2. Feedback and experiences with any of these are welcome:

• Amazon RDS: Fully managed and integrates well with the AWS ecosystem. Supports multiple engines like MySQL, PostgreSQL, and SQL Server.
• Amazon Aurora: Cloud-native and optimized for performance. Compatible with MySQL and PostgreSQL, with serverless deployment options.
• Microsoft SQL Server: A well-established enterprise option offering strong analytics capabilities, especially for teams using other Microsoft tools.
• Google Cloud SQL: Fully managed MySQL/PostgreSQL hosted on Google Cloud. A solid choice for stacks already built on GCP.
• Oracle Database: Delivers enterprise-grade performance and security. While potentially more than a startup may initially need, the cloud version is becoming more startup-friendly.

Startups or professionals with firsthand experience choosing among these solutions are encouraged to share what worked well, what could have been done differently, and why certain options were chosen.