The index of the changed document in the result set immediately after
this DocumentChange (i.e. supposing that all prior DocumentChange
objects and the current DocumentChange object have been applied).
Is -1 for 'removed' events.
oldIndex
oldIndex:number
The index of the changed document in the result set immediately prior to
this DocumentChange (i.e. supposing that all prior DocumentChange objects
have been applied). Is -1 for 'added' events.
A
DocumentChange
represents a change to the documents matching a query. It contains the document affected and the type of change that occurred.