Draw an entity-relationship diagram that describes the following business environment. The Super Baseball League wants to maintain information about...

Draw an entity-relationship diagram that describes the following business

environment.

The Super Baseball League wants to maintain information about its teams, their coaches,

players, and bats. The information about players is historic. For each team, the league

wants to keep track of all of the players who have ever played on the team, including the

current players. For each player, it wants to know about every team the player ever played

for. On the other hand, coach affiliation and bat information is current, only.

The league wants to keep track of each team’s team number, which is unique, its name, the

city in which it is based, and the name of its manager. Coaches have a name (which is only

assumed to be unique within its team) and a telephone number. Coaches have units of

work experience, which are described by the type of experience and the number of years

of that type of experience. Bats are described by their serial numbers (which are only

unique within a team) and their manufacturer’s name. Players have a player number that

is unique across the league, a name, and an age.

A team has at least one and usually several coaches. A coach works for only one team.

Each coach has several units of work experience or may have none. Each unit of work

experience is associated with the coach to whom it belongs. Each team owns at least one

and generally many bats. Currently and historically, each team has and has had many

players. To be of interest to the league, a player must have played on at least one and

possibly many teams during his career. Further, the league wants to keep track of the

number of years that a player has played on a team and the batting average that he

compiled on that team.