Draw a separate ER diagram for each description below. Your ER diagrams should be as simple as possible while accurately representing the described problem. Pay careful attention to phrasing such as "can", "must", "zero or more" etc. Sometimes human understanding is required, for example: something described as an $"$ID$"$ implies uniqueness, other times, uniqueness is described with other terminology. Use weak entity sets where appropriate.

Draw an ER diagram that represents chess players, games, and events. The specification of the information we need to store is as follows:

Players:

A chess Player has a name and an Elo rating $($Links to an external site.$).$

A Player can play in any number of chess Games.

A Player can not have the same name as any other Player.

Events:

A chess Event has a name, a site, and a date.

An Event can not have the same name and site and date as another Event, but they can have up to two of these values in common.

An Event is host to zero or more chess Games.

Games:

A chess Game has a round, a result, and a list of moves.

A Game is played by two Players $($one as white and one as black$).$ Every game must have exactly one white and one black player, and it must be identifiable who plays as white and who plays as black.

A Game takes place at an Event.

A Game can not have the same two players as white and black during the same round as any other Game at the same Event. In other words, if Player A plays as white against Player B as black during round $5$ at Event X$,$ then A and B can not play against each other $($as white and black respectively$)$ again during round $5$ at Event X$.$

The result is of the form $"$W$","$B$",$ or $"$D$",$ meaning white won, black won, or draw, respectively. The list of moves is plain text in pgn notation $($Links to an external site.$)$ of the form $"1.$e$4$ e$52.$Nf$3...".$ The moves can be up to $1000$ characters. Note: for this assignment, a Player's Elo rating is not taken from a pgn file $($we are only using pgn for the moves$).$ Assume a Player's Elo is constant.