Choosing relational DB for a small virtual server with 1Gb RAM

I am trying to find a decent relational database that would run on a small server, would be easy to administer and have much community love. I need a lightweight relational database for my personal Ubuntu server with only 1Gb of RAM. It would be used for occasional reads and writes, so high performance is not required. I considered popular options like MySQL and PostgreSQL, but those consume too much resources, even MariaDB may be too heavy since other projects should run on my server too. I considered Firebird, but it turned out to be not very intuitive for me and troubleshooting is difficult without much community-generated guides. I'm wondering if it's worth learning a niche database like Firebird for small pet projects. Are there any alternatives that require minimal RAM, have intuitive administration, drivers and ORM, and community support?