Contexts and Aliases are means to resolve loops/traps in 
universe designs. Contexts are used to specify which of the 
paths should be used when more than one path is possible 
from one table to another in a loop. Contexts are used in 
the scenarios where two or more many-to-one joins converge 
on a single table. Whereas Aliases are used to resolve the 
loops by duplicating the table and defining separate paths 
when one-to-many join links to a table which is again 
linked to another one-to-many join.