


The addition, deletion, modification and query functions implemented by mysql in php
This article mainly introduces the addition, deletion, modification and query functions implemented by mysql in php. Interested friends can refer to it. I hope it will be helpful to everyone.
List code
<?php $con = mysql_connect("localhost:3306","root",""); if (!$con) { die('Could not connect: ' . mysql_error()); } mysql_select_db("test", $con); $result = mysql_query("SELECT * FROM user"); echo "<table border='1'> <tr> <th>Username</th> <th>Password</th> </tr>"; while($row = mysql_fetch_array($result)) { echo "<tr>"; echo "<td>" . $row['username'] . "</td>"; echo "<td>" . $row['password'] . "</td>"; echo "</tr>"; } echo "</table>"; mysql_close($con); ?>
Delete
<?php $con = mysql_connect("localhost","root",""); if (!$con) { die('Could not connect: ' . mysql_error()); } mysql_select_db("test", $con); mysql_query("DELETE FROM user WHERE username = '$_POST[username]'"); mysql_close($con); ?>
Add
<?php $con = mysql_connect("localhost:3306","root",""); if (!$con) { die('Could not connect: ' . mysql_error()); } mysql_select_db("test", $con); $sql = "INSERT INTO user (username,password) VALUES ('$_POST[username]','$_POST[password]')"; if (!mysql_query($sql,$con)) { die('Error: ' . mysql_error()); } echo "1 record added"; mysql_close($con); ?>
Modify
<?php $con = mysql_connect("localhost","root",""); if (!$con) { die('Could not connect: ' . mysql_error()); } mysql_select_db("test", $con); mysql_query("UPDATE user SET password = '$_POST[password]' WHERE username = '$_POST[username]'"); mysql_close($con); ?>
<html> <head> <title>用PHP向数据库中实现简单的增删改查</title> </head> <body> <br /> <h1>Insert:</h1> <form action="insert.php" method="post"> username:<input type="name" name="username"/> <br /> password:<input type="password" name="password"/> <input type="submit" value="submit"/> </form> <br /><hr /><br /> <h1>Delete</h1> <form action="delete.php" method="post"> username:<input type="name" name="username" /> <br /> Are you sure?<input type="submit" value="sure" /> </form> <br /><hr /><br /> <h1>Update</h1> <form action="update.php" method="post"> username:<input type="name" name="username"/> <br /> You want to change your password into:<input type="password" name="password"/> <input type="submit" value="submit"/> </form> <br /><hr /><br /> </body> </html>
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