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PHP Basic

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PHP Superglobals

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PHP Advanced

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PHP OOP

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MySQL Database

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PHP XML

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PHP Reference

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Text lesson

MySQL Delete Data

Delete Data From a MySQL Table Using MySQLi and PDO

The DELETE statement is used to remove records from a table.

DELETE FROM table_name
WHERE some_column = some_value

Note the WHERE clause in the DELETE syntax: it specifies which record or records should be deleted. If the WHERE clause is omitted, all records will be deleted!

Let’s examine the “MyGuests” table:

id	firstname	lastname	email	reg_date
1	John	Doe	[email protected]	2014-10-22 14:26:15
2	Mary	Moe	[email protected]	2014-10-23 10:22:30
3	Julie	Dooley	[email protected]	2014-10-26 10:48:23

The following examples delete the record with id=3 from the “MyGuests” table:

Example (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();
?>

Example (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);
?>

Example (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;
?>

After deleting the record, the table will appear as follows:

id	firstname	lastname	email	reg_date
1	John	Doe	[email protected]	2014-10-22 14:26:15
2	Mary	Moe	[email protected]	2014-10-23 10:22:30