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I am getting this error when I try to connect to my database Fatal error: Call to undefined function pg_connect()...
The same piece of codes have worked without any changes to previous versions of php. A quick google search has reveiled that is most likely that php was not correctly build with PostgreSQL. I may be wrong though this is my code to connect.

<?php
// Database host
$db_host = "localhost";
// Database user
$db_user = "username";
// Database password
$db_pswd ="password";
// Database name
$db_name = "mydbname";

// Connect to the database
$pg = pg_connect("host=$db_host user=$db_user password=$db_pswd
dbname=$db_name") or die ("Can't connect to database");
?>