Week 06 6min Logical Design Sign-off, Data Dictionary

Produced with CyberLink PowerDirector 24Week 06 of the SWE4304 Databases module is titled Logical Design Sign-off, Data Dictionary, and Assessment 1 Packaging. During this week, the focus shifts from merely sketching diagrams to producing a rigorous, implementation-ready specification. Students do not write any SQL during this week; instead, they polish their logical designs and prepare their Assessment 1 evidence.
Here is a detailed breakdown of the topics and activities covered in Week 06:
1. Design Sign-Off and Integrity Rules Students run a comprehensive quality control check on their Entity-Relationship Diagrams (ERDs) and normalised relations. They are expected to document key constraints in plain English, specifically focusing on three types of integrity:
* Domain Integrity: Ensuring attribute values are valid in terms of data type, format, and allowed ranges.
* Entity Integrity: Guaranteeing that every table has a unique, non-null primary key.
* Referential Integrity: Ensuring that foreign keys correctly match a referenced primary key (or are explicitly allowed to be NULL).
2. The Data Dictionary To prevent ambiguity when it comes time to implement the database, students build a project data dictionary. For each table and attribute, this metadata document must record:
* The business meaning and definition of the data element.
* The planned data type and length.
* Nullability and default values.
* Domain rules (like specific patterns or allowed sets).
* Key notes, such as whether an attribute acts as a Primary Key (PK) or Foreign Key (FK).
3. Physical Considerations (Conceptual Level) While physical database implementation happens later, Week 06 introduces high-level physical and security concepts:
* Indexes: Students learn that indexes are physical structures used to speed up data retrieval, and they practice identifying candidate columns (like those frequently searched, joined, or sorted) without writing the code to create them.
* Denormalisation: The materials briefly revisit normalisation versus denormalisation, noting that while denormalisation can speed up read-heavy queries, students must keep their designs in Third Normal Form (3NF) unless they provide explicit written justification.
* Least Privilege: Students are introduced to the security concept of planning separate roles (e.g., admin, application, read-only reporting) that only receive the minimum permissions necessary.
4. Assessment 1 Packaging and Traceability The final major task of the week is assembling the Assessment 1 Design Report and its accompanying evidence pack.
* Report Structure: The suggested report format includes an introduction, a requirements summary, the conceptual ERD, the mapping to relational tables, normalisation evidence, the data dictionary, and validation checks.
* The Evidence Pack: Students compile versioned ERD exports (PDF/PNG), step-by-step normalisation tables, peer review notes, and a change log into an appendix.
* Traceability: A core grading requirement is proving the logic end-to-end. Every business requirement must map to a specific ERD element, and students must write strong justification paragraphs explaining why they made specific choices (like choosing a surrogate key over a natural key).

Видео Week 06 6min Logical Design Sign-off, Data Dictionary канала Atheer Mahir