so I have this add-on running w/ 1.5.5e and I'm noticing in my error logs that "Invoice" or admin/invoice.php throws this error message:
[29-Aug-2017 09:13:20 America/New_York] Request URI: /my-special-admin-named-folder/invoice.php?oID=106944, IP address: xx.xxx.149.155
#1 mysql_query() called at [/home/content/xx/5902262/html/my-special-admin-named-folder/invoice.php:356]
[29-Aug-2017 09:13:20 America/New_York] PHP Warning: mysql_query(): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2) in /home/content/62/5902262/html/my-special-admin-named-folder/invoice.php on line 356
[29-Aug-2017 09:13:20 America/New_York] Request URI: /my-special-admin-named-folder/invoice.php?oID=106944, IP address: xx.xxx.149.155
#1 mysql_query() called at [/home/content/xx/5902262/html/my-special-admin-named-folder/invoice.php:356]
[29-Aug-2017 09:13:20 America/New_York] PHP Warning: mysql_query(): A link to the server could not be established in /home/content/xx/5902262/html/my-special-admin-named-folder/invoice.php on line 356
[29-Aug-2017 09:13:20 America/New_York] Request URI: /my-special-admin-named-folder/invoice.php?oID=106944, IP address: xx.xxx.149.155
#1 mysql_fetch_array() called at [/home/content/xx/5902262/html/my-special-admin-named-folder/invoice.php:358]
[29-Aug-2017 09:13:20 America/New_York] PHP Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in /home/content/xx/5902262/html/my-special-admin-named-folder/invoice.php on line 358
...if I drill down into this as best as my n00b skills allow, I see that line 354's sql query of $dbc echos as something I can run in phpmyadmin successfully, but I'm not familiar w/ the db connection and how that works to figure this one out. Actually commenting out from line 355 of ```
$result = mysql_query($dbc);
$cv = $row[1];
...keeps the error from throwing, but it doesn't pull the formatting...
$dbc="select currency, currency_value from " . TABLE_ORDERS . " where orders_id ='" . $_GET['oID'] . "'"
...all in all this doesn't effect the output for me (that I can tell), but I'd imagine if you had customized currency value formatting it wouldn't work.