would imaging you won't be processing the whole lot! So the first thing is to edit them down. When I'm shooting or a models portfolio I may take 400 images, but only 20 or so will be editied. Say the 10 I like best and the 10 the model does. With a wedding you may need to pick out the best 20-30 to get good coverage of all the key bits and all the group shots.
So perhaps the thing to do would be to make a list of the final images you want: The church/registary office inside, the couple comming out, confetti being thrown, getting in the car. Then all the essential groups - bride and groom, brides family, grooms family, bride and groom + parents etc. Then may be one or two of the speeches and half a dozen candids from the reception? I have never shot a weding, so I may be a bit of on what is expected.
Remember giving them one cracking well edited shot of each "scene" will be better for them than 10 almost the same. Can you really imagine them looking through all 900, or even worse sitting down with each relation and making them look through all 900!!
Onc you have them thinned out to a sensible number I'd think about setting a schedule to do them without you getting lazy and bored. Maybe 10 per night?
You will need to go through them individually, but you may be able to save some time but grouping them into similarly lit sets and applying the same raw conversion to each before getting into the detailed work.
Depending on your editing skill level this could take a while - for portraits I reckon on between 10-30 mins per image, depending largley on how good the models skin/make-up is. Using the healing brush on blemishes can take for ever, but is essential for this kind of stuff. Don't be tempted to do any global skin softening as you'll end up with the bride looking like a plastic doll.