php中数据库连接mysqli和mysql的区别

<?php 
$host="127.0.0.1";
$userName="root";
$password="";
$dbName="db_database25";
$connID=mysqli_connect($host,$userName,$password);
mysqli_select_db($connID,$dbName);
mysqli_query($connID,"set names gbk");
$query=mysqli_query($connID,"select id from tb_article");
while($result=mysqli_fetch_array($query)) {
	echo "<div>".$result["id"]."<div>";
}
?>

<?php 
$host="127.0.0.1";
$userName="root";
$password="";
$dbName="db_database25";
$connID=mysql_connect($host,$userName,$password);
mysql_select_db($dbName,$connID);
mysql_query("set names gbk");
$query=mysql_query("select id from tb_article");
while($result=mysql_fetch_array($query)) {
	echo "<div>".$result["id"]."<div>";
}
?>

1、mysql_select_db和mysqli_select_db的参数刚好相反。

2、mysql_query比mysqli_query少一个连接对象参数。

字符串中输出：.$result["id"]. 注意前后有需要加点。