XQuery: Add support for Exists() and DoesntExist() #334
Description
Currently if I want to check only for the existence of some records, I have to fetch the records and test the count, while we can do the check directly on the db and save some network traffic.
Suggestion:
var isFound = db.Query("Table").Where("Some Conditions here").Exists();
var isNotFound = db.Query("Table").Where("Some Conditions here").DoesntExist();