tl;dr: Use ,omitempty, and if you need to worry about the difference between a zero value and null/not specified, do what the GitHub API does and use a pointer. Both json and bson support the ,omitempty tag. For json, “empty values are false, 0, any nil pointer or interface value, and any array, slice, map, … Read more
You can use “$$REMOVE”: This system variable was added in version 3.6 (mongodb docs) db.collection.aggregate([{ $group:{ field: { $push: { $cond:[ { $gt: [“$A”, 0] }, { id: “$_id”, A:”$A” }, “$$REMOVE” ] } }, secondField:{ $push: “$B” } } ]) In this way you don’t have to filter nulls.
Finally I successfully install the mgo project. I think it will be helpful for beginners, so I answer it here. First, we need GOPATH Define a env variable GOPATH, which is your project root directory, and it should have a sub dir src. For me, I define it to E:\WORKSPACE_GO\mgo, then create a sub dir … Read more
I faced similar error and added –authenticationDatabase parameter and it worked while we connecting to a remote MongoDB Use the similar below format in your code : $mongorestore –host databasehost:98761 –username restoreuser –password restorepwd –authenticationDatabase admin –db targetdb ./path/to/dump/