?
Solved

ERD Relationiships

Posted on 2007-04-05
3
Medium Priority
?
420 Views
Last Modified: 2010-05-18
Can someone please verify if i have the ERD correct - Any suggestions or opinons are greatly appreciated.

1.     The five entities identified are SoccerGame, Field, Team, Player, Referee, SoccerGameRule.
2.     Here are the relationships:
Each SoccerGame is played on one and only one Field; each Field hosts zero, one or more SoccerGame.
Each Field has zero, one or more FieldFeature; each FieldFeature is part of one and only one Field.
Each Attribute can participate in zero, one or more FieldFeature; each FieldFeature has one and only one Field.
Each Team has eleven and only eleven players; each Player is part of one and only one Team.
Each SoccerGame has one and only one Referree; each Referree arbiters zero, one or more SoccerGames.
Each SoccerGame has one and only one (Home) Team; each (Home) Team is part of zero, one or more SoccerGames.
Each SoccerGame has one and only one (Away) Team; each (Away)Team is part of zero, one or more SoccerGames.
3.     Further define relationships with cardinalities – Interesting to note is that a team can have exactly 11 players, and soccer game can have exactly two playing teams and one referee.
4.     select Primary Keys – see selected Primary Keys on the Figure 1 below. They are self-explanatory.
5.     determine Foreign Keys – see selected Foreign Keys on the Figure 1 below. . They are self-explanatory.

 

 



0
Comment
Question by:shoris
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
3 Comments
 
LVL 11

Accepted Solution

by:
dready earned 2000 total points
ID: 18861423
I'm not sure about these 2:
Each Field has zero, one or more FieldFeature; each FieldFeature is part of one and only one Field.
Each Attribute can participate in zero, one or more FieldFeature; each FieldFeature has one and only one Field.

Depends on what is in the FieldFeature table and the Attribute table. Also, thes tables are not mentioned under 1.

Furthermore: A team normally has 16 players, 11 on the field plus 5 extra players, that can play part of the game. And there are 3 referees, one on the field and 2 on the sideline.

0
 

Author Comment

by:shoris
ID: 18861434
Good points Dready.. I am not a soccer player but a friend of mine had me compile this.. :) I am going to have further look into your suggestions.. Good points.. thanks so much for replying so fast
0
 
LVL 6

Expert Comment

by:twintai
ID: 18861569
This is an interesting question. It's been a while since I have seen a conceptual question.

In any event, by my understanding your going to need about 7-8 entities. Note the following points.

1) For the SoccerGame: You would need an associative entity between SoccerGame and Team because you don't want to put the Home team and away team in one record where someone could mistakenly put a team as home and away. Call the associative entity "GameTeams" or something. It will look as follows:

GAMETEAMS
---------------
Autonumber
SoccerGamePK (FK)(PK)
TeamPK (FK)(PK)
HomeAway(PK)

With the above, you would be able to enter the same team as home as away. Of course, GAMETEAMS autonumber will have to be a foreign key in SoccerGame

2) As dready noted, the "Each Field has zero, one or more FieldFeature..." and "Each Attribute can participate in zero, one or more FieldFeature..." if off. With this, you would need to add two more entities, FieldFeature & Attributes


I didn't see the figure you were referring to but the final breakdown as I see it is as follows:

SOCCERGAME
-----------------
Autonum (PK)
FieldPK (FK)
GameTeamsAutoNum (FK)
RefereePK (FK)

GAMETEAMS
---------------
Autonumber
SoccerGamePK (FK)(PK)
TeamPK (FK)(PK)
HomeAway(PK)

TEAM
-------
Autonum (PK)

TEAMPLAYERS
-----------------
Autonum
TeamPK (FK)
PlayerPK (FK)

PLAYER
---------
Autonum (PK)

FIELD
-------
Autonum (PK)
FieldFeaturePK (FK)

FIELDFEATURE
------------------
Autonum (PK)
AttributePK (FK)

ATTRIBUTE
-------------
Autonum (PK)


0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

It’s been over a month into 2017, and there is already a sophisticated Gmail phishing email making it rounds. New techniques and tactics, have given hackers a way to authentically impersonate your contacts.How it Works The attack works by targeti…
Microsoft Access is a place to store data within tables and represent this stored data using multiple database objects such as in form of macros, forms, reports, etc. After a MS Access database is created there is need to improve the performance and…
With Microsoft Access, learn how to specify relationships between tables and set various options on the relationship. Add the tables: Create the relationship: Decide if you’re going to set referential integrity: Decide if you want cascade upda…
Add bar graphs to Access queries using Unicode block characters. Graphs appear on every record in the color you want. Give life to numbers. Hopes this gives you ideas on visualizing your data in new ways ~ Create a calculated field in a query: …
Suggested Courses

777 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question