Go でデータベース行をマップのスライスに効率的に変換するにはどうすればよいですか?

package main

import (
    "database/sql"
    "fmt"

    _ "github.com/go-sql-driver/mysql"
    "github.com/jmoiron/sqlx"
)

type Place struct {
    ID      int
    Telcode int
}

func main() {
    db, err := sqlx.Open("mysql", "user:password@tcp(localhost:3306)/database")
    if err != nil {
        fmt.Printf(err)
        return
    }

    rows, err := db.Query("SELECT * FROM place ORDER BY telcode ASC")
    if err != nil {
        fmt.Printf(err)
        return
    }

    places := []map[string]interface{}{}
    for rows.Next() {
        rowMap := make(map[string]interface{})

        if err := rows.MapScan(rowMap); err != nil {
            fmt.Printf(err)
            return
        }

        places = append(places, rowMap)
    }

    fmt.Println(places)
}