I need to translate the following MySQL sentences in PHP to Postgresql
Config.php File
MySQL
$mysqli = new mysqli($db_host, $db_username, $db_password, $db_name);
I tried: (Postgresql)
$db = pg_connect($db_host, $db_username, $db_password, $db_name);
MySQL:
$get_total_rows = 0;
$results = $mysqli->query("SELECT COUNT(*) FROM menu");
if($results){
$get_total_rows = $results->fetch_row(); 
}
//break total records into pages
$total_groups= ceil($get_total_rows[0]/$items_per_group);
I tried: (Postgresql) I don't know if I need really to change anything, I just change the name of my variable since it is different in my config.php file
$get_total_rows = 0;
$results = $db->query("SELECT COUNT(*) FROM menu");
if($results){
$get_total_rows = $results->fetch_row(); 
}
//break total records into pages
$total_groups= ceil($get_total_rows[0]/$items_per_group);
MySQL
if($_POST)
{
//sanitize post value
$group_number = filter_var($_POST["group_no"], FILTER_SANITIZE_NUMBER_INT, FILTER_FLAG_STRIP_HIGH);
//throw HTTP error if group number is not valid
if(!is_numeric($group_number)){
    header('HTTP/1.1 500 Invalid number!');
    exit();
}
//get current starting point of records
$position = ($group_number * $items_per_group);
//Limit our results within a specified range. 
$results = $mysqli->prepare("SELECT id, name, message FROM paginate ORDER BY id ASC LIMIT $position, $items_per_group");
$results->execute(); //Execute prepared Query
$results->bind_result($id, $name, $message); //bind variables to prepared statement
echo '<ul class="page_result">';
while($results->fetch()){ //fetch values
    echo '<li id="item_'.$id.'"><span class="page_name">'.$id.') '.$name.'</span><span class="page_message">'.$message.'</span></li>';  
}
echo '</ul>';
$mysqli->close();
}
Have not idea how to put this into Postgresql
Thank you so much