Normalization

De-normalized database form

First, we combine every attribute in the entire model into one single relation - Universal Relation R.

R(
    user_id,
    email,
    username,
    password,
    date_created,
    shipping_address,
    telephone_number,
    admin_type,
    discount_percentage,
    points_collected,
    artist_id,
    artist_name,
    artist_description,
    artist_photo,
    release_id,
    title,
    record_label,
    genre,
    release_date,
    cover_photo,
    duration,
    song_id,
    song_name,
    song_duration,
    product_id,
    format,
    price,
    product_description,
    stock,
    order_id,
    payment_method,
    purchase_date,
    points_earned,
    points_used,
    status,
    modification_id,
    date_modified,
    type_of_modification,
    discount,
    wishlist_id,
    quantity,
    price_at_purchase,
    added_at,
    release_ordinal,
    type,
    song_ordinal
)

Functional dependencies

FD01: user_id → email, username, password, date_created, shipping_address, telephone_number
FD02: email → user_id
FD03: username → user_id
FD04: user_id → admin_type, discount_percentage
FD05: user_id → points_collected
FD06: artist_id → artist_name, artist_description, artist_photo
FD07: release_id → title, record_label, genre, release_date, cover_photo, duration
FD08: song_id → song_name, song_duration
FD09: product_id → release_id, format, price, product_description, stock
FD10: order_id → user_id, payment_method, purchase_date, points_earned, points_used, status
FD11: modification_id → admin_id, date_modified, type_of_modification, discount
FD12: wishlist_id → user_id
FD13: user_id → wishlist_id
FD14: (order_id, product_id) → price_at_purchase, quantity
FD15: (wishlist_id, product_id) → added_at
FD16: (release_id, artist_id) → release_ordinal, release_artist_type
FD17: (song_id, artist_id) → song_ordinal

Candidate keys and primary key

1NF decomposition

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2NF decomposition

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3NF decomposition

…

BCNF if possible

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Final result and discussion