Is the Nikon D5100 good for wedding photography?
Does the Nikon D5100 has the capacity of taking shots for a wedding ceremony?
Added (1). I forgot to mention over the nikon d3200
Within its budget range it's probably the most capable camera for this, due to its good low light performance.
Having a good, fast (low f-number) lens will be even more important though, and the skill of the person using both lens and camera is the most important thing of all.
A D5100 would be suitable for a casual guest taking photos. For the primary event photographer it would likely not suffice.
-> You can get decent shots with it if you know how to use it, but don't expect to produce marketable wedding photography with it for paying customers.
Considering I started my wedding photography with a D90 (which doesn't handle high ISO as well as the 5100), I can tell you that it could do a wedding ceremony. However, you will be pushing it to its absolute limits! It really will depend on the venue you are shooting at and what lenses you have to use.
I would recommend renting or buying prime lenses (f/1.8 or f/1.4) and/or pro-zooms (Nikon 17-55 2.8; Sigma 17-50 2.8 OS; Nikon 70-200 2.8 VRII). Do not depend on the kit lens to take your wedding pictures!
On a side note, make sure you shoot a wedding with at least two camera's if you're going to be the main photographer. The last thing you need is for your primary camera to break down in the middle of the ceremony!
Any DSLR is fine for wedding photography as long as you know how to use the camera properly.
Buying a nice camera won't magically enable you to take nice pictures.
More imporatant would be the lens.