How to create/drop mongoDB database and collections from a golang (go language) program.?

Issue

func DatabaseConnect() (db *mongo.Database, err error) {
    ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
    defer cancel()
    client, err := mongo.Connect(ctx, options.Client().ApplyURI("mongodb://localhost:27017"))
    if err != nil {
        return
    }
    db = client.Database("students")
    return
}

this above function connects to a database which is already present on mongoDB server. But can we write a function silimar to this one, which will create/drop a database and some collections also.

func HandleDatabases(){
// for deleting / creating / managing mongoDB databases and collections ?
}

Solution

Using MongoDB, databases and collections do not need to exist prior to using them.

You can run queries against non-existing databases and collections, which will not result in an error, but obviously won’t return any documents. When inserting documents into a non-existing database and/or collection, the database and/or collection will be created automatically.

To drop a database, simply use the Database.Drop() method. To drop a collection, simply use the Collection.Drop() method.

You only need to create a collection before using it if you want it to create with non-default, special properties. For that, you may use Database.CreateCollection().

To find out which databases exist already on the server, you may use the Client.ListDatabases() or Client.ListDatabaseNames() methods.

To find out which collections exist already in a database, you may use the Database.ListCollections() or Database.ListCollectionNames() methods.

Answered By – icza

Answer Checked By – Pedro (GoLangFix Volunteer)

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