// Copyright 2013 The Go Authors. All rights reserved.// Use of this source code is governed by a BSD-style// license that can be found in the LICENSE file. package sql_test import (	"database/sql"	"fmt"	"log") var db *sql.DB func ExampleDB_Query() {	age := 27	rows, err := db.Query("SELECT name FROM users WHERE age=?", age)	if err != nil {		log.Fatal(err)	}	defer rows.Close()	for rows.Next() {		var name string		if err := rows.Scan(&name); err != nil {			log.Fatal(err)		}		fmt.Printf("%s is %d\n", name, age)	}	if err := rows.Err(); err != nil {		log.Fatal(err)	}} func ExampleDB_QueryRow() {	id := 123	var username string	err := db.QueryRow("SELECT username FROM users WHERE id=?", id).Scan(&username)	switch {	case err == sql.ErrNoRows:		log.Printf("No user with that ID.")	case err != nil:		log.Fatal(err)	default:		fmt.Printf("Username is %s\n", username)	}}