What potential issue can arise when using multiple queries within a PHP function?

When using multiple queries within a PHP function, one potential issue that can arise is that the connection to the database may be closed after the first query is executed, causing subsequent queries to fail. To solve this issue, you can ensure that the database connection remains open throughout the function by not closing the connection until after all queries have been executed. 

// Establish a database connection
$connection = mysqli_connect("localhost", "username", "password", "database");

// Check if the connection is successful
if (!$connection) {
    die("Connection failed: " . mysqli_connect_error());
}

// Perform multiple queries
$query1 = "SELECT * FROM table1";
$result1 = mysqli_query($connection, $query1);

$query2 = "SELECT * FROM table2";
$result2 = mysqli_query($connection, $query2);

// Close the database connection after all queries have been executed
mysqli_close($connection);

Keywords

SQL injection database connection mysqli prepared statements query execution.

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