beccahyland / iris_app Goto Github PK

purpose: ability to design / add foreign key relationships
id
region - varchar
shade - decimal(3,2)
meters from water - integer

'irises_location_fkey'

format irises into table view - graphs would be better

'iris_class'

display ALL irises at page load

DATABASE irisapp

TABLE irises
id - serial primary key
sepal length - decimal(2,1)
sepal width - decimal(2,1)
petal length - decimal(2,1)
petal width - decimal(2,1)
class - varchar
location - integer

1. CREATE TABLE classes(id SERIAL PRIMARY KEY, name VARCHAR(20));
2. INSERT INTO classes(name) VALUES ('Iris-setosa'); (etc. for 3 classes)
3. ALTER TABLE irises ADD COLUMN class_key INTEGER;
4. UPDATE irises SET class_key=1 WHERE class='Iris-setosa'; (etc. for 3 classes)
5. ALTER TABLE irises DROP COLUMN class;
6. ALTER TABLE irises ADD FOREIGN KEY (class_key) REFERENCES classes(id);
   foreign key is named irises_class_key_fkey
7. CREATE INDEX class_key_index ON irises (class_key);
8. ALTER TABLE irises RENAME COLUMN location TO location_key;
   (to match the new class_key column)

GET (2)

GET (2)

psql -d postgres -U iris_role