In this scenario, you do not have to worry, it will work. I’ll try to explain:
- 2 users submitting form at the same time. As long as you do not provide an _id yourself, wix-data will provide a unique _id for both, they will be separate entries in your collection
The problem arises ONLY if you try to generate some kind of a unique id (either _id or an id in another column, like “invoice number” that should be raised sequentially [990001, 990002, etc]). In that case, there is a freak chance that (assuming last used invoice number = 990002):
a)user A uses a function that looks up last number used and raises it by 1. Number 990003 is now written to collection as last number used.
b) user B uses the same function IN BETWEEN user’s A request and the writing back to the collection of 990003. We are talking milliseconds here, but it could occur. In that case, user A retrieves 990003 and so does B. They will still get a different _id from wix-data if you do not provide one yourself, so the info will not be mixed, you will have 2 rows with different _id’s but with the same invoice number (990003). Which could be bad. There is a solution for it, but it is not your problem in this scenario.
2)same thing: they both have a different _id, so they will not be mixed.
IN short: if rows carry a different _id, you are OK on database level. But, as described in 1) you ALSO want to add another unique id (like invoice number, part number, usually sequential), that’s where problems COULD arise in a high volume scenario (but it is solvable).
Hope this helps.