I have a scenario where I need to update about 1000000 items in a list. The list has event receivers registered to it that I would like to disable during the update. Since the number of items are quite big the script that does this will have to run for a loooong time. I have seen some examples where you disable the event firing but I'm not sure how SharePoint handles concurrent requests.
I have a console application that will make a system update for each item. My thought is to turn the event firing off right before the update and then turn it back on again as soon as it is finished. Is it possible that a user makes an update request on a list item (where the event firing should be enabled) during the time that my no-event update is processing? Or will SharePoint handle each request sequentially?