Atlassian Products Checker (tbox-atlassian.php) allows you to check for the latest available versions of Atlassian products and show your currently installed ones. The script is written in PHP and utilizes the curl_multi module to simultaneously poll multiple sites.
Here you can find the database schemas of Atlassian JIRA 7.x and Confluence 6.x. The GUI of JIRA and Confluence does not provide access to everything and does not show everything stored in databases. Sometimes you may get some unknown errors/exceptions in JIRA and Confluence logs, to troubleshoot them effectively you need to dive deeper than the GUI allows. That's why you need to be aware of how the database schema looks like to perform direct queries against a database. Also it is quite useful to extract more details to understand how to improve performance and clean out stale things.