anybody is familiar with this? can you please help me understand where can I find the other tables, Cases_1 and Employees_1? If I click on the relationship I can see these tables but I can't see that on the Main Page? are they some kind of being hidden?
Tables occuring in the relationship diagram with _1 , _2, ... usually are just copies of the original table (only in the diagram). They still represent the original table and links to this Cases_1 and Employees_1 will represent links to the original Cases and Employees table. So you will not find these tables as they are not existant. You can try this out yourself, by right click the relationship diagram, select 'show tables' and adding a couple of the tables twice or more. You will see tables with _1, _2 etc behind their names popping up. 

