Golang在PostgreSQL中找不到现有表

I'm trying to learn databases in golang with postgresql by tutorials.

Although database exists, program gives output:

go run dbase.go

2017/01/02 20:43:07 pq: database "bookstore" does not exist

this is psql output:

deneme=# \l
                             List of databases
   Name    |  Owner   | Encoding | Collate | Ctype |   Access privileges   
-----------+----------+----------+---------+-------+-----------------------
 bookstore | postgres | UTF8     | C       | C     | 
 deneme    | postgres | UTF8     | C       | C     | 

and this is the relevant part of go code:

const (
    DB_USER     = "postgres"
    DB_PASSWORD = "root"
    DB_NAME     = "bookstore"
)

func main() {
    dbinfo := fmt.Sprintf("user=%s password=%s dbname=%s sslmode=disable",
        DB_USER, DB_PASSWORD, DB_NAME)
    db, err := sql.Open("postgres", dbinfo)
    if err != nil {
        log.Fatal(err)
    }

Also changing connection code to this gives the same output:

db, err := sql.Open("postgres", "postgres://postgres:root@localhost/bookstore?sslmode=disable")

Thanks;