List,
I have a data modeling problem. That much, I know. The question is how do I
model this? (Below.)
I'm making a database which will store pseudo-genetic data. It's a basic
many-to-many setup::
create table person(
name varchar(32) primary key
);
create table gene(
name varchar(32) primary key
);
create table person_gene(
person varchar(32) references person(name),
gene varchar(32) references gene(name)
);
If my vague memories of high-school biology are right, then I think you might be on the wrong track here. Great. This is important as I need to be able to ask questions like "who
carries gene 'x'?" as well as "what genes does person 'y' carry?" But then
things get thorny...
I also need to store the properties of the individual genes (the alleles). This
is akin to an instance of one of the many gene classes in my application code.
So I make more tables::
create table hair(
id serial primary key,
density float,
thickness float
);
create table eye(
id serial primary key,
pupil_type int
);
How do I store a reference to this data? I'd add a column to the person_gene
table, but it points to what? I can't reference a column name because they're
all stored in different tables. I also can't store them in the same table, as
they all store different data. Do I store the *table name* itself in a column
of the gene_table? (Smells like a klude.)
Aren't alleles related to genes? (Hence my previous remark)
If that's the case, you'd add a gene foreign key to each allele table and then store which alleles are related to a person instead of which genes are related to a person. The genes then follow from the alleles. Is that closer to what you're after?
Alban Hertroys -- If you can't see the forest for the trees, cut the trees and you'll find there is no forest.
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