missing { } causing error that table does not exist if using db table with prefix

Issue Summary

I use a mysql db with prefixes as the database is running a multisite configuration.  This module installed fine but when I went to view the Aggregator summary, there was an error saying that a number of the aggregator summary tables did not exist.  I checked and the install was fine and the tables did exist and I traced it to some missing brackets around table names in the module file. 

For example, the table name should be:
{aggregator_summary_item} 
but instead was just:
aggregator_summary_item

When I put the missing brackets into the file, the module worked fine.  I have attached a modified version of the module. 
The missing brackets are on the following lines:  1142, 1151, 1417, 1663, 1719
-Aaron