Calendar in php and html - php

Question

I'm developing a calendar with reservations in HTML and PHP (I do not know how to do otherwise). Only I have a problem with formats and data.
First of all I have problems regarding the date, I had to set it as "integer" on Postgresql and consequently on the form html as text (and this is the first thing I would like to change).
Same thing regarding the timetable.
form.php
<?php
if (isset($_POST['submit']) && $_POST['submit']=="invia")
{
$titolo = addslashes($_POST['titolo']);
$testo = addslashes($_POST['testo']);
$str_data = strtotime($_POST['data']);
include 'config.php';
$sql = "INSERT INTO appuntamenti (titolo,testo,str_data ) VALUES ('$titolo', '$testo', '$str_data')";
if($result = pg_query($sql))
{
echo "Inserimento avvenuto con successo.<br>
Vai al Calendario";
}
}else{
?>
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post">
Titolo:<br>
<input name="titolo" type="text"><br>
Testo:<br>
<textarea name="testo" cols="30" rows="8"></textarea><br>
Data:<br>
<input name="data" type="text" value="gg-mm-aaaa"><br>
Orario:<br>
<input name="hour" type="time" ><br> -->
<input name="submit" type="submit" value="invia">
</form>
<?php
}
?>
appuntamenti.php
<?php
if(isset($_GET['day']) && is_numeric($_GET['day']))
{
$day = $_GET['day'];
include 'config.php';
$sql = "SELECT * FROM appuntamenti WHERE str_data=$day";
$result = pg_query($sql);
if(pg_num_rows($result) > 0)
{
while($fetch = pg_fetch_array($result))
{
$id = stripslashes($fetch['id']);
$titolo = stripslashes($fetch['titolo']);
$testo = stripslashes($fetch['testo']);
$data = date("d-m-Y", $fetch['str_data']);
$hour = date("hh-mm", $fetch['hour']);
echo "Appuntamenti del <b>$data</b> delle <b>$hour</b><br>" . $titolo . "<br>" . $testo . "<br>
Cancella |
Modifica
<hr>";
}
}
}
?>
In this case i receive the date in the correct way ( but the user inserts this like text, and i don't want to do this. ) and the hours likes 0101-0101.
How can i solve?
Thanks you all