Problems pulling data from additional DB Tables

I inherited a site running EE 1.7.0. In this site we get external data in a daily download that we import into our database (the same database that the EE tables are in.. exp_). These tables have a different prefix (sig_). So, we have one database with several tables (exp_ and sig_). We use straight PHP to pull in this data and display on certain pages of our site using this type of code:

<?php

global $DB;

$query_source .= ” FROM sig_cruise_offers c ” . “INNER JOIN sig_cruise_current_pricing p ON c.offer_id = p.offer_id ” . “INNER JOIN sig_cruise_ships s ON c.product_id = s.product_id ” . “INNER JOIN sig_cruise_suppliers sup ON c.sup_id = sup.sup_id “;

etc. etc.

more queries, joins, etc.

display data

?>

I’ve installed the latest version of EE (2.x), imported all or our EE data and SIG data in a DEV environment. Everything in EE2 works great except that i cannot get any of the SIG tables to show using the same code as we used in 1.7.

So, am i missing something? I do use a plugin called Select2 to pull in a drop down list using the SIG Table and this works fine.

Were we using some type of extension in 1.7 that i don’t have now? Basically, i just want to make a page that pulls in data from one or more of these SIG tables. Any ideas? Thanks!