Play alert sound after bank query (PHP + MYSQL)

Your javascript function was probably not working (I believe) because you were "tapping" the sound before the audio element was created. For example:

<?php
//seleciona o numero de linhas da tabela
$consulta = $conexao->query("SELECT COUNT(*) FROM toyota_base where statuz='NOVO'");

//atribui a variavel $num_rows o numero de linhas
$num_rows = $consulta->fetchColumn();

//verifica se o numero de linhas é maior que 0 (zero)
if($num_rows > 0){
    //toca o som de alerta
    echo "<script> play();</script>"; // <-- O elemento audio só vai ser criado daqui algumas linhas,
                                      //     não tem como ele ser tocado ainda.
}

?>

<audio id="audio">
   <source src="alert.mp3" type="audio/mp3" />
</audio>

<script type="text/javascript">

   audio = document.getElementById('audio');

function play(){
   audio.play();
}

</script>

If you're using jQuery, change your echo to:

echo "<script> jQuery(document).ready(play);</script>";

If it's not, here is a question (in English) about how to create the ready event with pure javascript.

Or just put if and element audio :

<?php 
    if($num_rows > 0){
?>
<audio id="audio" autoplay>
   <source src="alert.mp3" type="audio/mp3" />
</audio>
<?php
    }
?>

So the audio element will only be created if there are records in the table and will not generate unnecessary bandwidth by downloading the audio when it does not (as with your embed solution). Note also that the autoplay attribute causes the audio to play automatically when it is ready and does not need to create any javascript function for it.

I found the answer:

Instead of using my javascript function, I just used the line:

<embed src='alert.mp3'width='1' height='1'>

And that solved the problem.

Final code:

<?php  

//seleciona o numero de linhas da tabela
$consulta = $conexao->query("SELECT COUNT(*) FROM toyota_base where statuz='NOVO'");                            

//atribui a variavel $num_rows o numero de linhas
$num_rows = $consulta->fetchColumn();

//verifica se o numero de linhas é maior que 0 (zero)                       
if($num_rows > 0){
    //toca o som de alerta
    echo "<embed src='alert.mp3'width='1' height='1'>";
}

?>

That's it, for those who need it someday, the solution is there.