Mysqli操作数据库

$mysql_server_name  = "localhost";
$mysql_username 　　= "root"; 
$mysql_password 　　= "root"; 
$mysql_database 　　= "db_name"; 
$mysql_table 　　　 = "table_name"; 

// 新建连接
$mysqli = new mysqli($mysql_server_name, $mysql_username, $mysql_password);

/** 调试连接是否正常 */
if ($mysqli->connect_errno) {
    die($mysqli->connect_error);
    exit();
}

//删除数据库
$sql_delete_db = "drop database $mysql_database";
if ($mysqli->query($sql_delete_db) === true) {
    die("ok");
} else {
    die($mysqli->connect_error);
}

//创建数据库
$sql_create_db = "create database $mysql_database";
if ($mysqli->query($sql_create_db) === true) {
    die("ok");
} else {
    die($mysqli->error);
}

//选择数据库
$mysqli->select_db($mysql_database);

//创建数据表
$sql_create_table = "create table $mysql_table(id int NOT NULL AUTO_INCREMENT,PRIMARY KEY(id),name varchar(15),age int)";
if ($mysqli->query($sql_create_table) === true) {
   die("ok");
} else {
   die($mysqli->error);
}

//删除数据；
$sql_delete = "delete from $mysql_table where age = 200";
if ($mysqli->query($sql_delete) === true) {
    die("ok");
} else {
    die($mysqli->error);
}

//插入新数据；
$age = rand(12, 80);
$sql_inset = "insert into $mysql_table (name,age) value ('flying_$age',$age)";
if ($mysqli->query($sql_inset) === true) {
    die("ok");
} else {
    die($mysqli->error);
}
//查询数据；
$sql_select = "select * from  $mysql_table order by age";
if ($result = $mysqli->query($sql_select)) {
    printf("Select returned %d rows.
", $result->num_rows);
    while ($row = $result->fetch_row()) {
        println("$row[0]  $row[1]  $row[2]");
    }
    $result->close();
}


// 更新表中数据
$sql_update = "update $mysql_table set age = 200 where age < 67";
if ($mysqli->query($sql_update) === true) {
   die("ok");
} else {
   die($mysqli->error);
}
//关闭连接
$mysqli->close();