DB에 성공적으로 연결이 완료된 후 해당 테이블의 SELECT 쿼리를 실행하는 방법

Go Example - Select 모든 결과 출력

참고 : https://zetcode.com/golang/mysql/

https://tutorialedge.net/golang/golang-mysql-tutorial/

func API_TEST(w http.ResponseWriter, r *http.Request) {
	fmt.Println("Function TEST!!")

	db := dbConn()
	defer db.Close()

	keys, err := db.Query("SELECT publickey, privatekey FROM Holder_Key")
	if err != nil {
		log.Fatal(err)
	}
	defer keys.Close()

	for keys.Next() {
		var keylist KEY_LIST
		err := keys.Scan(&keylist.PublicKey, &keylist.PrivateKey)
		if err != nil {
			log.Fatal(err)
		}

		fmt.Println(keylist)
	}
}

output : 
Function TEST!!
{6t3pJkJcrqQkt9CRCL3eofHJGAPFoF5YRaYzVxTArEeS 5psurmHBJMwmErjk4vn8UAF3rKWm2sTxZ74Tf2tU975PC5y5byKwGcWEdGyRrJq9rqRsTtciJ1UDh99vzUmjDVFk }

Go Example - Select 단일 출력

참고 : https://tutorialedge.net/golang/golang-mysql-tutorial/

/*
 * Tag... - a very simple struct
 */
type Tag struct {
    ID   int    `json:"id"`
    Name string `json:"name"`
}

var tag Tag
// Execute the query
err = db.QueryRow("SELECT id, name FROM tags where id = ?", 2).Scan(&tag.ID, &tag.Name)
if err != nil {
    panic(err.Error()) // proper error handling instead of panic in your app
}

log.Println(tag.ID)
log.Println(tag.Name)