I have had a few database projects obsoleted when the DB maker has closed down or was bought and the app shot down, shied me away from depending on commercial/activation limited options.<p>So last time, I went for open source for the DB selected MySQL and haven't look back (now its MariaDB, easy transition) It was open source, easy to use, I could have an installation backup ready if needed, and very popular, might not be shiny new but was dependable for what we use it for.<p>You may need to find some distributed solution for an OSS DB (or roll your own, depends on the complexity/size), but where there's a will, and good community resources, there is certainly a way. Likely means data conversion, no matter the DB, unless your distributed data, IDs, and tables are basically generic fields, there will need to be some conversion done for any alternative.<p>Also, if you want long-term, don't go for cutting edge, boring and reliable is better.