I have a struct like this:
type SavedData struct {
ID bson.ObjectId `bson:"_id"`
Data string
Date time.Time
}
I also have my
collection := database.C("coll_name")
How do I retrieve the last inserted entry in this collection ?
Thank you
The accepted answer is 5 years old. This should work Today with mongodb driver
collection.FindOne(ctx, bson.M{"$natural": -1})
unknown top level operator: $natural if I try this. Do you reckon what can it be?Apparently mongoDB is by default sorted by insertion time according to this question so you can just skip the first N elements of the collection like so.
var myData SavedData
dbSize, err := collection.Count()
if err != nil {
return err
}
err = c.Find(nil).skip(dbSize-1).One(&myData)
if err != nil {
return err
}
or you can search in the reverse order
c.Find(bson.M{ "$natural": -1 }).One(&myData)
You have to use options with mongo-driver if you want to get the latest document in the collection
import(
...
"go.mongodb.org/mongo-driver/mongo/options"
)
myOptions := options.FindOne()
myOptions.SetSort(bson.M{"$natural":-1})
collection.FindOne(ctx, bson.M{}, myOptions)
