Changes between Initial Version and Version 1 of Proof of 1N form

Timestamp:

01/27/26 23:33:28 (13 days ago)

Author:

213087

Comment:

--

Proof of 1N form

@@ +1 @@
+=== Step 0: Initial Unnormalized Relation (UNF) ===
+
+The system initially stores all information in a single relation:
+
+USER_WEDDING_VENUE(user_id, user_first_name, user_last_name, user_email, wedding_id, wedding_date, wedding_budget, venue_id, venue_name, venue_type, venue_capacity, booking_id, booking_date, start_time, end_time)
+
+This relation contains attributes describing multiple entities (User, Wedding, Venue, Booking).
+Storing all data together leads to redundancy and update anomalies.
+
+Identified Functional Dependencies (FDs):
+
+-user_id → user_first_name, user_last_name, user_email
+-wedding_id → wedding_date, wedding_budget, user_id
+-venue_id → venue_name, venue_type, venue_capacity
+-booking_id → venue_id, wedding_id, booking_date, start_time, end_time
+
+=== Step 1: Decomposition to 1NF (First Normal Form) ===
+
+Definition of 1NF:
+
+-A relation is in 1NF if all attributes contain atomic values
+-No repeating groups or multivalued attributes exist
+-Each row is uniquely identifiable by a key
+
+The relation is decomposed based on entity responsibility while preserving all data.
+
+=== R1: USER ===
+
+|| Table || Attributes ||
+|| R1 || user_id, user_first_name, user_last_name, user_email ||
+
+Primary Key:
+-user_id
+
+Functional Dependency:
+-user_id → user_first_name, user_last_name, user_email
+
+Justification:
+-All attributes are atomic
+-All attributes depend only on user_id
+-user_id uniquely identifies a system user
+-No repeating groups exist
+
+Conclusion:
+-R1 satisfies 1NF
+
+=== R2: WEDDING ===
+
+|| Table || Attributes ||
+|| R2 || wedding_id, wedding_date, wedding_budget, user_id ||
+
+Primary Key:
+-wedding_id
+
+Foreign Key:
+-user_id → USER(user_id)
+
+Functional Dependency:
+-wedding_id → wedding_date, wedding_budget, user_id
+
+Justification:
+-Each wedding is uniquely identified by wedding_id
+-user_id represents ownership of the wedding
+-All non-key attributes depend solely on wedding_id
+
+Conclusion:
+-R2 satisfies 1NF
+
+=== R3: VENUE ===
+
+|| Table || Attributes ||
+|| R3 || venue_id, venue_name, venue_type, venue_capacity ||
+
+Primary Key:
+-venue_id
+
+Functional Dependency:
+-venue_id → venue_name, venue_type, venue_capacity
+
+Justification:
+-Venue attributes describe a single independent entity
+-Attributes are static and not dependent on other relations
+-venue_id uniquely identifies a venue
+
+Conclusion:
+-R3 satisfies 1NF
+
+=== R4: VENUE_BOOKING ===
+
+|| Table || Attributes ||
+|| R4 || booking_id, venue_id, wedding_id, booking_date, start_time, end_time ||
+
+Primary Key:
+-booking_id
+
+Foreign Keys:
+-venue_id → VENUE(venue_id)
+-wedding_id → WEDDING(wedding_id)
+
+Functional Dependency:
+-booking_id → venue_id, wedding_id, booking_date, start_time, end_time
+
+Justification:
+-A booking represents a reservation of a venue for a specific wedding
+-booking_id uniquely identifies each reservation
+-All attributes depend directly on booking_id
+
+Conclusion:
+-R4 satisfies 1NF
+