PHP——连接数据库

PHP作为客户端连接MySQL服务器只需要三步：
（1）连接MYSQL服务器
     $conn = mysqli_connect($host,$uname,$upwd,$dbname,$port);
（2）执行SQL语句
     $sql = "INSERT/DELETE/UPDATE/SELECT ..."; //此处的SQL语句内部无需添加分号
     mysqli_query($conn,$sql);
（3）处理执行结果
     mysqli_affected_rows($conn); //获取影响的行数
     mysqli_fetch_row($result); //从结果集中读取一行
（4）(可以省略)关闭数据库连接

     mysqli_close($conn);

<?php

	$conn = mysqli_connect('localhost','root','123456','database1',3306);
	$sql = "DELETE FROM emp WHERE eid=1000";
	$result = mysqli_query($conn,$sql);

	if($result){
		echo "删除成功";
	}else{
		echo "删除失败";
	}
?>

<?php
	$did = 60;
	$dname = 'fanhua';
	$loc = 'Bei Jing';
	echo $did;
	$conn = mysqli_connect('localhost','root','','tedu',3306);
	//$sql = "INSERT INTO dept(did,dname,loc) VALUES(50,'feixing','New York')"; //可执行
	$sql = "INSERT INTO dept(did,dname,loc) VALUES('$did','$dname','$loc')";//记得加引号

	$result = mysqli_query($conn,$sql);

	if($result){
		echo "操作成功";
	}else{
		echo "操作失败";
	}
?>

--------------------------------------

<?php
	$did = $_REQUEST['did'];
	$dname = $_REQUEST['dname'];
	$loc = $_REQUEST['loc'];
	echo $did;
	$conn = mysqli_connect('localhost','root','','tedu',3306);
	//$sql = "INSERT INTO dept(did,dname,loc) VALUES(50,'feixing','New York')"; //可执行
	$sql = "INSERT INTO dept(did,dname,loc) VALUES('$did','$dname','$loc')";//记得加引号

	$result = mysqli_query($conn,$sql);

	if($result){
		echo "操作成功";
	}else{
		echo "操作失败";
	}
?>

-------------------------

建立公共文件

<?php
    //init.php
	$conn = mysqli_connect('127.0.0.1','root','','database1',3306);
	mysqli_query($conn,"SET NAMES UTF8");
?>

包含这个文件

<?php
	
	require('init.php');

	@$n = $_REQUEST['uname'] or die('uname required');
	@$p = $_REQUEST['upwd'] or die('upwd required');

	$sql = "INSERT INTO xz_user VALUES(NULL,'$n','$p')";
	$result = mysqli_query($conn,$sql);

	if($result){
		echo "操作成功";
	}else{
		echo "操作失败";
	}


?>