How can the user improve the SQL query in the PHP code to avoid errors and ensure accurate data retrieval?

The user can improve the SQL query in the PHP code by using prepared statements to prevent SQL injection attacks and ensure accurate data retrieval. Prepared statements separate the SQL query from the user input, which helps to avoid errors and ensure the correct data is retrieved from the database. 

// Improved PHP code with prepared statements to avoid errors and ensure accurate data retrieval

// Establish a database connection
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

$conn = new mysqli($servername, $username, $password, $dbname);

// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// SQL query with prepared statement
$stmt = $conn->prepare("SELECT * FROM users WHERE username = ?");
$stmt->bind_param("s", $username);

// Set the username variable
$username = "example_username";

// Execute the query
$stmt->execute();

// Get the result set
$result = $stmt->get_result();

// Fetch data from the result set
while ($row = $result->fetch_assoc()) {
    echo "Username: " . $row["username"] . "<br>";
}

// Close the statement and connection
$stmt->close();
$conn->close();

Keywords

SQL query PHP code data retrieval errors accuracy

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