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PHP删除数据从MySQL


删除数据从一个MySQL表使用的MySQLi和PDO

DELETE语句用来从表中删除记录:

DELETE FROM table_name
WHERE some_column = some_value

注意:在删除语法WHERE子句:WHERE子句指定哪些记录或应该被删除的记录。 如果省略WHERE子句,所有记录都将被删除!

要了解更多有关SQL,请访问我们的SQL教程

让我们来看看"MyGuests"表:

ID 名字 电子邮件 reg_date
1 约翰 母鹿 [email protected] 2014年10十四时26分15秒
2 玛丽 [email protected] 2014年10月23日十时22分30秒
3 朱丽叶 杜利 [email protected] 2014年10月26日10时48分23秒

下面的实施例删除与ID = 3的记录在"MyGuests"表:

实施例(MySQLi Object-oriented)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// sql to delete a record
$sql = "DELETE FROM MyGuests WHERE id=3";

if ($conn->query($sql) === TRUE) {
    echo "Record deleted successfully";
} else {
    echo "Error deleting record: " . $conn->error;
}

$conn->close();
?>

实施例(MySQLi Procedural)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

// sql to delete a record
$sql = "DELETE FROM MyGuests WHERE id=3";

if (mysqli_query($conn, $sql)) {
    echo "Record deleted successfully";
} else {
    echo "Error deleting record: " . mysqli_error($conn);
}

mysqli_close($conn);
?>

实施例(PDO)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDBPDO";

try {
    $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
    // set the PDO error mode to exception
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    // sql to delete a record
    $sql = "DELETE FROM MyGuests WHERE id=3";

    // use exec() because no results are returned
    $conn->exec($sql);
    echo "Record deleted successfully";
    }
catch(PDOException $e)
    {
    echo $sql . "<br>" . $e->getMessage();
    }

$conn = null;
?>

记录被删除后,该表将是这样的:

ID 名字 电子邮件 reg_date
1 约翰 母鹿 [email protected] 2014年10十四时26分15秒
2 玛丽 [email protected] 2014年10月23日十时22分30秒