In the MongoDB aggregation framework, I was hoping to use the $unwind operator on a map. Looks like it's not possible. case class MatchStatus( totalRows: Int, fullMatch: Int, noMatch: Int,...

in the following image i am using $project aggregation. i need to compare whether text feild is equals to 'A' or not using $cond. If this boolean condition is true it should return 1 otherwise 0. but ...

I am creating a database for a dentist. On Tuesdays, the secretary sends reminders to all the patients who have an appointment for the next week. The query I used in SQL is: SELECT P.Name , P....