I have just finished publishing a storage plugin for Microsoft SQL Server here:
With this plugin you can store your flows, configuration, settings, sessions, and library into a Microsoft SQL Server database as opposed to JSON files. The plugin was inspired by the MongoDB storage plugin by adibenmati (https://github.com/adibenmati/node-red-mongo-storage-plugin).
I created this because there is a great degree of comfort level with SQL Server among the teams I am working with - they already have backup plans in place, security, and generally prefer all data live under one roof. Also, SQL Server has great JSON support nowadays should I ever need to query / update / compute columns on the data. Fortunately the simple storage API made this come together with just a few hours of work.
One known bug with the current release - I am able to save library entries just fine but am not connecting the dots somewhere on what properties need to be present on the object when selecting to install an item from the library. Perhaps somebody out there will have a pointer on that.
Let me know if anybody has any problems!