field indicating last modification of a documont in mongodb
I am building an API over my mongodb cluster. Each call for the API should return only the newest values or the values that have been modified seen the last call. I thought i need to add a field to each ducoment either representing the insertion timestamp or an auto incrementing field.
in mongodb how do i save the last instance of archive entities
I have a a stream of entity transactions. Each transaction is a json consists of _id of the entity and a time of the transaction (there are many more fields). I want to save in the last transaction of each entity in my mongodb colection.
meaning i want to replace an existing mongo record if it has the same _id and the new time is great the the current time. If the _id does not exists yet, then I want to insert it as a new record.
Aggregations on arrays Mongodb
Aggregations query in mongodb
My MongoDB Query is returning 0 results even though I am sure its correct
I have never used mongo db, I made a mongoDB data base called MilitaryMarathonDB and a collection called CIS4340
here is a sample record:
{“_id”:{“$oid”:”662aef4884f1ffcadbc2edc0″},”place;gender;first;last;bib #;age;place;gender place;clock time;net time;branch;distance”:”194;M;JACOB;PELLETIER;3053;29;12111;4981;7:43:21;7:20:05;Army;marathon”,”Unnamed: 1″:{“$numberDouble”:”NaN”}}