I have a table with users, each row looks like this:
{
id: <user's id>,
email: <user's email>
}
Where id is the primary key and there's a secondary index for email.
I want to add a user only if no other use with the same email exists. Normally I would use two queries for this: getAll(<user's email>, {index: 'email'}) to make sure the email is not taken, followed by insert({email: <user's email>} but these are two separate queries (i.e. not an atomic operation).
Is there a way to check-and-set atomically using getAll?
Note: I know it's possible to do it with get as shown here but that doesn't work with getAll
You can't do atomic operations on secondary indexes, unfortunately. The best thing to do would probably be to add another emails table where the primary key is the email address.