This stack part is quite young (at least it seems that way to me) and I'm not sure if such question would be tolerable.
No, this particular Stack Exchange site (that's what they're called) is quite mature, and we're well prepared to help people, so long as it fits in with our scope, and as to:
I want to ask specific question - what database should I choose for analytics, here's my research of what I know and here is problems that I'm worried about in my case.
We can't let you just say "here's a bunch of links, and here's a summation of each, now which should I choose" but if you said "So I see that XYZ supports ABC, but that TUV doesn't support ABC, and my intended use case is DEF (which everyone seems to think ABC is good for), should I choose TUV or do I really need ABC and so the only obvious choice is XYZ?"
And if the question is:
I could choose mongo, or I could choose raven, but I'm not sure which I need, can you help me decide?
Then I'm going to suggest you haven't done any research at all.