Lazy summer project: build a basketball app.
Date: 29 Jun 2006 11:21:53 -0700
All, it's been a long time since I've done a from scratch database design. What follows is a shameless appeal for anyone with some database design expertise, a few extra minutes, and desire to help out - to offer any criticisms/advice they see fit. I'll conclude the opening paragraph with an apology to those without said expertise, few extra minutes, or desire to help; for the time wasted on reading the opening paragraph (and a suggestion to read no further/waste no further time).
My dad is a huge D3 college basketball fan, and during the season, he attempts to keep daily tabs on the entire division (hundreds of teams). Last year, he approached me for help. He'd been using dozens of Excel sheets to track the games, and was having tremendous difficulties keeping up. Data entry was a nightmare - all games needed to be modified in two places (once for each team). Due to lack of data integrity, his sheets were riddled with errors/typos. And reporting was even worse - he spent hours each weekend manually sorting sheets, summing functions, etc., in order to answer such simple questions as "Which team has the best record", and "Next weekend, are there any undefeated teams playing each other".
Anyway, at the time, I helped him out by writing some ugly Excel macros for data synchronization (allowing him to enter a score once and have it posted in both places) - but it was conditioned on his promise to let me design a relational database for the next season.
So here I sit - it's been a long time since I've done a from-scratch relational design, but it's a slow afternoon, so I figured I'd start some ER planning.
I start with a Team entity, with each team having a division attribute
(1, 2, or 3), a conference attribute, a college name, a shorthand name
/ abbreviation, and a city/state (pk will be division, conference, college name). I can hand this entity over to my dad right now, and he can start populating it. But I'm getting a bit stuck on the next step.
At first, I thought, I'll need a simple Game relation. But I think
this will need to be a super relation of sorts - because certain
attributes of tournament games are different than non-tournament games
(e.g. existence of a home/away team; existence of the name of the
tournament; a tournament round number; etc.).
Another odd characteristic of the Game relation is that I can't come up
with a decent natural key while retaining symmetry of opponents (team A
vs. team B == team B vs. team A).
If I recall correctly, in a game between some team1 and team2, both
(Game Date, Team1) and (Game Date, Team2) are viable candidates - no
team will ever play two games on the same day. But I'd have to break the symmetry in order to get a natural key (I think).
So, I'm now leaning towards introducing an artificial Game entity with a surrogate Game_id, e.g. <Game_id(pk), scheduled date>, and also introducing a Opponent relation <Game ID (pk / fk on Game), Team (pk / fk on Team), Points scored, ...>. I'd have to enforce some application-level constraints (e.g. each game_id must exist exactly two times in Opponent (if at all)), but it does keep a nice symmetry.
Anyway, I've got ample time to think this one through - and my thought is "if I build this right the first time, I can design some front-ends for data loading, some views for data extraction, etc..., and my dad might have a nice toy to play with for years to come".
So, having said that - I'm open to any design advice or criticisms
anyone may have to offer. My best idea right now:
Team <division, conference, college, a shorthand name, city, state>
Game <Game_id (pk), Date>
NonTourneyGame <Game_id (pk - fk on Game.Game_id)> TourneyOpponent <Game_id (pk - fk on TourneyGame.game_id), Team_fk
NonTourneyOppenent <Game_id (pk - fk on NonTourneyGame.game_id), Team_fk (pk), Home_Away_Ind, Points_scored> Received on Thu Jun 29 2006 - 20:21:53 CEST