One strategy for relational schema design is to start by putting all attributes into one relation, and then decompose the relation according to various depedencies. Here is an example.

The United States has a presidential election every four years. Each presidential candidate has a designated vice presidential candidate. Each state has a designated number of electoral votes. In all states except Nebraska and Maine, the candidate that receives the most popular votes of citizens in the state secures all electoral votes of the state. The candidate with a majority of the electoral votes becomes the next president of the United States.

Putting the above information together and we have a table:

Election $($Candidate$,$ Vice$\_$president, Year, State, Electoral$\_$votes, Popular$\_$votes$),$

or in abbreviation,

Election $($C$,$ V$,$ Y$,$ S$,$ E$,$ P$)$

with the following functional dependencies among the attributes:

CY $->$ V

VY $->$ C

SY $->$ E

CSY $->$ P

You are asked to do the following:

List all keys in the table.

Indicate which normal form the table is in$.$

If the table is not in BCNF$,$ decompose it to tables that are in BCNF$.$

Determine whether the decomposition is dependency preserving or not.