Find duplicate records in MongoDB
How would I find duplicate fields in a mongo collection. I’d like to check if any of the “name” fields are duplicates. { … Read more
aggregation-framework
MongoDB SELECT COUNT GROUP BY
I am playing around with MongoDB trying to figure out how to do a simple SELECT province, COUNT(*) FROM contest GROUP BY province … Read more
MongoDB: Combine data from multiple collections into one..how?
How can I (in MongoDB) combine data from multiple collections into one collection? Can I use map-reduce and if so then how? I … Read more
Get names of all keys in the collection
I’d like to get the names of all the keys in a MongoDB collection. For example, from this: db.things.insert( { type : [‘dog’, … Read more
Retrieve only the queried element in an object array in MongoDB collection
Suppose you have the following documents in my collection: { “_id”:ObjectId(“562e7c594c12942f08fe4192”), “shapes”:[ { “shape”:”square”, “color”:”blue” }, { “shape”:”circle”, “color”:”red” } ] }, { … Read more
Update MongoDB field using value of another field
In MongoDB, is it possible to update the value of a field using the value from another field? The equivalent SQL would be … Read more