Cannot connect PHP to Postgres - php

Question

I have had the hardest time getting PHP to talk to Postgres SQL. Here is my setup:
Ubunu Desktop 13.10
PHP 5.5.3
Postgres 9.1.10
Apache 2.4.6
Netbeans 7.4 with xdebug
Everything is working fine. I am able to enter and retrieve data in the Postgres Database fine from the command line but not in PHP. Here are the lines of code that I am using to connect:
$dbConn = new softwareDB('localhost', 'postgres', 'root', 'softwareuitest');
...
$results = $dbConn.getClients();
while($client = pg_fetch_result($results)){
echo '<option value=\"'.$client.'\">'.$client.'</option>';
}
The softwareDB class constructor is as follows:
Class softwareDB {
private $conn;
function _construct($host, $user, $password, $dbname) {
$connectString =
'host=' . $host .
' port=5432' .
' user=' . $user .
' password=' . $password .
' dbname' . $dbname;
$this->conn = pg_connect($connectString);
}
...
public function getClients() {
global $conn;
return pg_query($conn,'getClients','SELECT * FROM clients');
}
...
}
When running the code nothing happens... I see nothing in the Apache log file, nothing in the postgres log, nothing from the debugger, and only HTML (without query data) in the output.
I cannot post images yet but here are the details about Postgres from phpInfo():
PDO
PDO Drivers | pgsql
pdo_pgsql
version 9.1.9
module 1.0.2
revision $id$
pgsql
PostgreSQL(libpq) | PostgreSQL 9.1.9 on x86_64-unknown-linux-gnu, compiled by gcc (Ubuntu/Linaro 4.8.1-10ubuntu1) 4.8.1, 64-bit
allow_persistent is on

Answer 1

You have two main issues. The first is a typo; PHP class instance methods are called via the arrow operator. It should be...
$results = $dbConn->getClients();
The second is your use of global $conn. You don't have a variable named $conn, global or not. What you do have is a member property $conn which you may reference by prefixing it with $this, eg
public function getClients() {
return pg_query($this->conn, 'SELECT * FROM clients');
}
Looking further, I would suggest that if you're going to abstract DB details away in your softwareDB class, you might as well do it completely. I'd go with something like this
class softwareDB {
private $conn;
public function __construct($host, $user, $password, $dbname) {
$this->conn = pg_connect(sprintf('host=%s port=5432 user=%s password=%s dbname=%s',
$host, $user, $password, $dbname));
if ($this->conn === false) {
throw new Exception(pg_last_error());
}
}
public function getClients() {
$result = pg_query($this->conn, 'SELECT * FROM clients');
return pg_fetch_all($result);
}
}
I'm not too familiar with the PostgreSQL Functions so you may need to tweak this but the general idea is that code using your softwareDB class doesn't need to know anything about postgres or other DB operations.