Apply the Chain Algorithm to the mediator query
With the following adornments at the sources for R, S, and T. If there is more than one adornment for a predicate, either may be used.
In each case: v
i. Indicate all possible orders in which the subgoals can be resolved.
ii. Does the Chain Algorithm produce an answer to the query?
iii. Give the sequence of relational-algebra operations needed to compute the intermediate relation X at each step and the result of the query.