silverstripe-environmentcheck/code/checks/DatabaseCheck.php

<?php
/**
 * This file contains a number of default environment checks that you can use.
 */


/**
 * Check that the connection to the database is working, by looking for records in some table.
 * By default, Member will be checked.
 * 
 * @param $checkTable The table that will be checked.
 */
class DatabaseCheck implements EnvironmentCheck {
	protected $checkTable;
	
	function __construct($checkTable = "Member") {
		$this->checkTable = $checkTable;
	}
	
	function check() {
		$count = DB::query("SELECT COUNT(*) FROM \"$this->checkTable\"")->value();
		
		if($count > 0) {
			return array(EnvironmentCheck::OK, "");
		} else {
			return array(EnvironmentCheck::WARNING, "$this->checkTable queried ok but has no records");
		}
	}
}