Up until recently I was using mongo to try and stem to tide of massive MySQL upgrades to system servers, however, after reading this:
I have halted production of a mongo version of my site until mongo would gain more stability.
Some have suggested I use the _change within couche DB to create a new mongo object which would solve the main issues within mongo db atm but I'm not sure about it.
I have looked into other DB's such as redis and Cassandra but I have since ditched Cassandra as you have to design for your queries and that's just too restricting for my site (bad modulisation). I'm not really looking for joins etc, I'm just looking for the ability to search within a row instead of just the columnfamily id's as it can make programming quite hard when trying to add new functionality. It would be great for a search engine or something but not so good for a real website like facebook in it's entirty (instead of just in its mail search).
I was wondering what experiences people on here have had with trying to get a workable solution to the SQL speed issues. Is there a silver bullet db for it all or is it just a case of gritting your teeth with MySQL or another SQL db if you want reliability?
Maybe a cross between a form of caching and SQL (I noticed facebook uses heavy caching on their wall pages etc...probably why).