CREATE TABLE product_media (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    product_id UUID NOT NULL REFERENCES products(id) ON DELETE CASCADE,
    media_id UUID NOT NULL REFERENCES media(id) ON DELETE CASCADE,
    position INT NOT NULL DEFAULT 0,
    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
    UNIQUE (product_id, media_id)
);

CREATE INDEX idx_product_media_product_id ON product_media(product_id);