Esempio n. 1
0
// reset cleans up after previous runs of this applications.
func reset(conn mongo.Conn) {
	log.Println("\n== Clear documents and indexes created by previous run. ==\n")
	db := mongo.Database{conn, "learn", mongo.DefaultLastErrorCmd}
	db.Run(mongo.D{{"profile", 0}}, nil)
	db.C("unicorns").Remove(nil)
	db.C("hits").Remove(nil)
	db.Run(mongo.D{{"dropIndexes", "unicorns"}, {"index", "*"}}, nil)
	db.Run(mongo.D{{"dropIndexes", "hits"}, {"index", "*"}}, nil)
}
Esempio n. 2
0
func chapter7(conn mongo.Conn) {

	log.Println("\n== CHAPTER 7 ==")

	db := mongo.Database{conn, "learn", mongo.DefaultLastErrorCmd}
	unicorns := db.C("unicorns")

	log.Println("\n== Create index on name. ==\n")

	err := unicorns.CreateIndex(mongo.D{{"name", 1}}, nil)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("\n== Drop index on name. ==\n")

	err = db.Run(mongo.D{
		{"dropIndexes", unicorns.Name()},
		{"index", mongo.IndexName(mongo.D{{"name", 1}})},
	}, nil)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("\n== Create unique index on name. ==\n")

	err = unicorns.CreateIndex(mongo.D{{"name", 1}}, &mongo.IndexOptions{Unique: true})
	if err != nil {
		log.Fatal(err)
	}

	log.Println("\n== Create compound index on name ascending and kills descending. ==\n")

	err = unicorns.CreateIndex(mongo.D{{"name", 1}, {"vampires", -1}}, nil)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("\n== Explain query. ==\n")

	var m mongo.M
	err = unicorns.Find(nil).Explain(&m)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("\n== Explain query on name. ==\n")

	m = nil
	err = unicorns.Find(mongo.M{"name": "Pilot"}).Explain(&m)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("\n== Enable profiling. ==\n")

	err = db.Run(mongo.D{{"profile", 2}}, nil)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("\n== Get profile data for query. ==\n")

	cursor, err := unicorns.Find(mongo.M{"weight": mongo.M{"$gt": 600}}).Cursor()
	if err != nil {
		log.Fatal(err)
	}
	expectFieldValues(cursor, "name", "Unicrom", "Ayna", "Kenny", "Leia", "Pilot", "Dunx")

	cursor, err = db.C("system.profile").Find(nil).Cursor()
	if err != nil {
		log.Fatal(err)
	}

	for cursor.HasNext() {
		var m mongo.M
		err := cursor.Next(&m)
		if err != nil {
			log.Fatal(err)
		}
	}
	cursor.Close()

	log.Println("\n== Profile queries that take longer than 100 ms. ==\n")

	err = db.Run(mongo.D{{"profile", 2}, {"slowms", 100}}, nil)
	if err != nil {
		log.Fatal(err)
	}
}