week 6

3.6 Structures for storing data

3.6.1 Understand the role of metadata in providing descriptions and contexts for data.

When data is created, stored, or transmitted, it often needs additional information to make it meaningful and useful. This is where metadata comes in. Metadata is often described as “data about data.” It provides descriptions, context, and structure that help people and systems understand, manage, and organise the main data.

Without metadata, a file, dataset, or digital object would just be raw content with no clear meaning. For example, a photo file would only contain pixel data, but metadata can add context such as when it was taken, who took it, the camera settings, and even GPS location. This descriptive information makes data easier to search, retrieve, interpret, and manage.

Definition and Purpose of Metadata

• Definition: Metadata is information that describes the characteristics, properties, or context of data. It does not alter the data itself but provides supporting details that enhance understanding and usability.

• Purpose:

  • To give context (e.g., who created the data, when, and why).

  • To aid organisation and retrieval (e.g., library catalogues, search engines).

  • To support data governance and security (e.g., permissions, classification).

  • To provide interoperability across systems (e.g., file sharing between applications).

Roles, Uses, and Examples of Metadata

1. Descriptive Metadata

• Role: Provides information about the content.

• Use: Used in catalogues, search engines, and digital libraries to help users find resources.

• Example: A library entry describing a book’s title, author, and ISBN.

• Compatible Software: Library management systems, online catalogues, search engines.

2. Structural Metadata

• Role: Describes how data is organised and related.

• Use: Ensures systems know how to present and link parts of data together.

• Example: A website sitemap XML file showing the hierarchy of web pages.

• Compatible Software: Web browsers, content management systems (WordPress, Drupal).

3. Administrative Metadata

• Role: Provides information on how to manage the data.

• Use: Supports digital rights management, storage, and file control.

• Example: A PDF document with embedded copyright information and file type details.

• Compatible Software: Adobe Acrobat, Windows Explorer (file properties), cloud storage (Google Drive, OneDrive).

4. Technical Metadata

• Role: Describes technical details of a file or dataset.

• Use: Enables correct use and interpretation of digital objects.

• Example: Photo metadata storing resolution, bit depth, and colour model.

• Compatible Software: Photoshop (EXIF data), Lightroom, data warehouses.

5. Provenance Metadata

• Role: Records the history and origin of the data.

• Use: Ensures trust and authenticity of data.

• Example: Audit trails in a database showing who edited a record and when.

• Compatible Software: SQL databases, SharePoint, Git version control.

Real-World Examples of Metadata

A Word document contains metadata such as author, word count, and last modified date.

A music file (MP3) includes metadata tags for artist, album, and genre.

A digital photograph stores EXIF metadata for camera model, GPS coordinates, and shutter speed.

A dataset in a data warehouse uses metadata to describe field names, data types, and relationships.

“Making Data Meaningful – The Power of Metadata”

Time: 30–40 minutes (including prep + presentation)

Instructions for Students

Part 1 – Explore Metadata (10 mins)
In small groups (2–3 students), open different types of files on your computer (e.g., Word document, PDF, photo, or MP3 file).
Right-click the file and check Properties (Windows) or Get Info (Mac).

Record the metadata you can find, such as:
- Author/creator
- Date created/modified
- File size
- Keywords/tags
- Technical details (resolution, encoding, etc.)

Part 2 – Research Case Studies (10–15 mins)
Research one real-world case study where metadata is essential. Examples could include:
- Photography – how EXIF metadata (camera settings, GPS location) is used in photo management or digital forensics.
- Music/Film – how metadata in MP3s/MP4s allows Spotify or Netflix to categorise and recommend content.
- Cybersecurity – how hidden metadata in documents (e.g., author names in leaked Word/PDF files) has exposed sensitive information.
- Libraries & Archives – how descriptive metadata helps catalogues and digital archives stay searchable.

Prepare 2–3 key points from your chosen case study to share.

Part 3 – Present Your Findings (10–15 mins)
Each group should prepare a short presentation (3–4 minutes) covering:
- Definition: What metadata is in your own words.
- Examples: Metadata you found in your own files.
- Case Study: The real-world use of metadata you researched.
- Impact: Why metadata is valuable in making data more useful and reliable.

Stretch / Challenge Task
Discuss as a group: Can metadata ever be a risk? (e.g., GPS location data in photos uploaded online, exposing personal info).
Suggest one security measure organisations can use to manage metadata safely.

3.6.2 Know the definition of file-based and directory-based structures and understand their purposes and when they are used.

All digital systems must store and organise data in ways that make it easy to access, manage, and retrieve. Two of the most common organisational models are file-based structures and directory-based structures.

• A file-based structure focuses on storing data in individual, stand-alone files. Each file is independent and may not directly connect with other files, meaning data can be duplicated or difficult to share between systems.

• A directory-based structure is more organised, using folders (directories) and subfolders (subdirectories) to group related files. This hierarchy makes it easier to navigate and manage large sets of data.

Both approaches are still used today, and the choice depends on data complexity, collaboration needs, and the scale of storage required.

File-Based Structures

Definition

A storage model where data is stored in independent files, often with no enforced relationships between them. Each file is self-contained.

Purpose & Use

• Simple and low-cost way to store and access data.

• Common for personal use, small systems, or applications where data doesn’t need to be shared widely.

• Used when performance and simplicity are more important than complex data relationships.

Examples & Case Studies

• Case Study 1 – Small Business Accounting:
  A local shop saves all its sales records in Excel spreadsheets and stores them as individual files (e.g., Jan_sales.xlsx, Feb_sales.xlsx). This is easy to set up but leads to duplication of customer details and makes cross-checking totals more time-consuming.

• Case Study 2 – Medical Practice (Legacy Systems):
  An older clinic database saves each patient’s record in a separate file. This makes searching slow and creates issues when patients have multiple files across departments.

Software Examples

• Microsoft Excel / Access (file-based storage)

• CSV or text files in data logging systems

• Legacy business systems

Directory-Based Structures

Definition

A hierarchical storage model where files are grouped into directories (folders) and subdirectories, providing a structured way to organise information.

Purpose & Use

• Provides a clear hierarchy and reduces duplication.

• Easier navigation and searching across large datasets.

• Common in operating systems, enterprise systems, and cloud storage where data is shared and must be controlled.

Examples & Case Studies

• Case Study 1 – Corporate File Server:
  An IT company uses a shared drive with directories like Projects > 2025 > ClientX > Reports. This makes it simple for teams to collaborate while keeping data well organised. Metadata (permissions, timestamps) helps manage access.

• Case Study 2 – University Learning Platform:
  A university stores student submissions in directories by course and module (Course > Module > StudentID). This ensures work is easy to locate and secure.

• Case Study 3 – Cloud Collaboration (Google Drive/SharePoint):
  Teams working remotely store documents in shared directories, ensuring all members see the same updated files without creating multiple versions.

You are going to investigate the difference between file-based and directory-based structures, using the case studies provided. Your task is to show your understanding by applying real-world reasoning and producing a short written or visual response.

Instructions

Part 1 – Compare the Structures (10 mins)

1. Write down two key features of file-based structures.
2. Write down two key features of directory-based structures.
3. Explain in your own words why a small business (e.g., local shop with sales spreadsheets) might choose a file-based structure instead of a directory-based one.
4. Explain why a university or IT company would prefer directory-based storage instead of file-based.


Part 2 – Case Study Scenarios (10 mins)
For each scenario below, decide whether a file-based structure or a directory-based structure would be best. Write 2–3 sentences explaining your choice.
Scenario A: A freelance photographer saves all their client photos. Each photoshoot needs to be kept separate but easy to find later.
Scenario B: A multinational corporation needs to share HR records across several countries, with access restrictions for different teams.
Scenario C: A student keeps lecture notes on their personal laptop. Each week’s notes are saved in Word files.

Part 3 – Reflection (5 mins)
In one short paragraph, explain which structure you personally use most often (on your own computer, cloud storage, or phone).
Why does that structure suit your needs?

Output Options
You can present you work as:
A written response (1–2 pages).
A diagram or mind map comparing file vs directory structures with examples.

3.6.3 Know the definition of hierarchy-based structure and understand its purpose and when it is used.

3.6.4 Understand the interrelationships between storage structures and data transformation.

Last Updated
2025-09-23 14:31:54