php操作数据库

都适、隶仁ミ2024-06-09 14:55

<?php

session_start();

#面向过程

function create_connection(){

$conn = mysqli_connect('127.0.0.1','root','123456','learn_2') or die("数据库连接失败");

mysqli_query($conn,"set names utf8");

return $conn;

}

#面向对象

function create_connection_opp(){

$conn = new mysqli('127.0.0.1','root','123456','learn_2') or die("数据库连接失败");

$conn->query("set names utf8");

#$conn->set_charset('utf8');

return $conn;

}

function test_mysqli_opp(){

$conn = create_connection_opp();

$sql = "select * from user";

$result =$ conn->query($sql);

//获取结果集行数

#echo $result->num_rows;

$rows =$ result->fetch_all();

var_dump($rows);

#关联数组的方式

$rows =$ result->fetch_all(MYSQLI_ASSOC);

var_dump($rows);

foreach ( $rows as$ row){

echo $row['username']."<br>" ;

echo $row['password'];

}

}

//mysql预处理功能

function mysqli_prepare_stmt(){

$conn =create_connection_opp();

$sql = "select * from user where username = ?";

//实例化prepared statement预处理对象

$stmt =$ conn->prepare($sql);

#实例化需要将参数进行绑定 "s"代表字符串 "i"整数 "d"小数 "b"二进制

$stmt-\>bind_param("s",$ username);

$username = 'zs';

#要获取查询结果，还需要绑定结果参数。不需要返回结果无需此操作

$stmt-\>bind_result($ username,$password);

#返回值bool ture执行成功 false执行失败

$stmt->execute();

#调佣结果并进行处理

$stmt->store_result();

while($stmt->fetch()){

echo $username,$ password,'<br>';

}

#输出行数

echo $stmt->num_rows.'<br>';

echo $stmt->affected_rows;

/**

* $sql = "select * from user where username = ? and password = ?";

* $stmt-\>bind_param("ss",$ username,$password);

*/

}

mysqli_prepare_stmt()

?>