diff --git a/classes/PgDatabase.php b/classes/PgDatabase.php
index cfde8bc..b86c6c3 100644
--- a/classes/PgDatabase.php
+++ b/classes/PgDatabase.php
@@ -1,5 +1,74 @@
 <?php
 
 class PgDatabase {
-	
+	private $db = null;
+
+	public function __construct() {
+		$instance = isset($_GET['instance']) ? trim($_GET['instance']) : null;
+		if ($instance === null) return;
+		$url = trim($_SERVER['REQUEST_URI'], '/');
+		$url = substr($url, 7); // api/vX/
+		$ps = explode('/', $url);
+		if ($ps[0] !== 'database') return;
+		$software = $ps[1];
+
+		if (!preg_match('/^[a-zA-Z0-9\.\-\_]+$/', $instance))
+			apiresult(['error' => 'instance parameter is not correctly formatted'], 400);
+		if (!preg_match('/^[a-zA-Z0-9\.\-\_]+$/', $software))
+			apiresult(['error' => 'software parameter is not correctly formatted'], 400);
+
+		$GLOBALS['IS_PHP'] = true;
+		require 'api/v1/config/get/mod.php';
+		unset($GLOBALS['IS_PHP']);
+
+		$found = false;
+		foreach ($GLOBALS['api_data']['hosts'][$software] as $ins_cfg) {
+			if ($ins_cfg['instance'] === $instance) {
+				$found = $ins_cfg;
+				break;
+			}
+		}
+		if ($found === false) return;
+		$config = [];
+		$config_raw = explode("\n", trim($found['config']));
+		foreach ($config_raw as $ln) {
+			$k = substr($ln, 0, strpos($ln,'='));
+			$v = substr($ln, strpos($ln,'=')+1);
+			$config[$k] = $v;
+		}
+
+		$this->db = pg_connect(
+			' host='.$config['psql_host'].
+			' port='.$config['psql_port'].
+			' dbname='.$config['psql_db'].
+			' user='.$config['psql_username'].
+			' password='.$config['psql_password'].
+		'') or apiresult('Could not connect to postgres: '.pg_last_error());
+	}
+
+	public function is_ok() {
+		return $this->db !== null;
+	}
+
+	public function query($sql) {
+		$result = pg_query($sql);
+		if (!$result) apiresult('The postgres query has failed: '.pg_last_error());
+		return $result;
+	}
+
+	public function fetch_all($sql) {
+		$data = [];
+		$result = $this->query($sql);
+		while ($line = pg_fetch_array($result, null, PGSQL_ASSOC)) {
+			$data []= $line;
+		}
+		pg_free_result($result);
+		return $data;
+	}
+
+	public function close($result=null) {
+		if ($result !== null)
+			pg_free_result($result);
+		pg_close($this->db);
+	}
 }