# Post-ERG Database Specification

Complete technical specification of the Post-ERG thesis database schema.

**Version:** 1.0  
**Database:** SQLite  
**Last Updated:** February 5, 2026

---

## 📋 Table of Contents

1. [Overview](#overview)
2. [Entity Relationship Diagram](#entity-relationship-diagram)
3. [Core Tables](#core-tables)
4. [Lookup Tables](#lookup-tables)
5. [Junction Tables](#junction-tables)
6. [Support Tables](#support-tables)
7. [Views](#views)
8. [Indexes](#indexes)
9. [Triggers](#triggers)
10. [Data Types Reference](#data-types-reference)
11. [Business Rules](#business-rules)
12. [Sample Queries](#sample-queries)

---

## Overview

### Purpose
Database for managing and publishing ERG final thesis projects (TFE - Travaux de Fin d'Études) and doctoral theses.

### Key Features
- Multi-author thesis support
- Multiple supervisors per thesis
- Flexible format types (web, audio, video, print, etc.)
- Access control (public, internal, restricted)
- File attachment management
- Keyword tagging system
- Full-text search capability
- Academic metadata tracking

### Database Size Estimates
- **Expected records**: 100-500 theses/year
- **Growth rate**: ~10-15% annually
- **Average record size**: ~5KB (metadata only)
- **File storage**: External (linked via file paths)

---

## Entity Relationship Diagram

```
┌─────────────┐       ┌──────────────────┐       ┌─────────────┐
│   authors   │◄──────│ thesis_authors   │──────►│   theses    │
└─────────────┘  1:N  └──────────────────┘  N:1  └─────────────┘
                                                         │
┌─────────────┐       ┌──────────────────┐              │
│supervisors  │◄──────│thesis_supervisors│──────────────┘
└─────────────┘  1:N  └──────────────────┘  N:1
                                                   
┌─────────────┐       ┌──────────────────┐              
│ keywords    │◄──────│ thesis_keywords  │──────────────┐
└─────────────┘  1:N  └──────────────────┘  N:1        │
                                                         │
┌─────────────┐       ┌──────────────────┐              │
│ languages   │◄──────│ thesis_languages │──────────────┤
└─────────────┘  1:N  └──────────────────┘  N:1        │
                                                         │
┌─────────────┐       ┌──────────────────┐              │
│format_types │◄──────│ thesis_formats   │──────────────┤
└─────────────┘  1:N  └──────────────────┘  N:1        │
                                                         │
┌─────────────┐                                          │
│orientations │──────────────────────────────────────────┤
└─────────────┘  1:N                              N:1   │
                                                         │
┌─────────────┐                                          │
│ ap_programs │──────────────────────────────────────────┤
└─────────────┘  1:N                              N:1   │
                                                         │
┌─────────────┐                                          │
│finality_types│─────────────────────────────────────────┤
└─────────────┘  1:N                              N:1   │
                                                         │
┌─────────────┐                                          │
│access_types │──────────────────────────────────────────┤
└─────────────┘  1:N                              N:1   │
                                                         │
┌─────────────┐                                          │
│license_types│──────────────────────────────────────────┤
└─────────────┘  1:N                              N:1   │
                                                         │
┌─────────────┐                                          │
│thesis_files │──────────────────────────────────────────┘
└─────────────┘  N:1
```

---

## Core Tables

### `theses`
**Purpose:** Main table storing thesis/dissertation information.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `identifier` | TEXT | YES | NULL | Unique identifier (e.g., "2025-002") |
| `title` | TEXT | NO | - | Thesis title |
| `subtitle` | TEXT | YES | NULL | Optional subtitle |
| `year` | INTEGER | NO | - | Academic year of submission |
| `is_doctoral` | BOOLEAN | NO | 0 | 0 = TFE (Master), 1 = Doctoral thesis |
| `orientation_id` | INTEGER | YES | NULL | FK to `orientations` |
| `ap_program_id` | INTEGER | YES | NULL | FK to `ap_programs` (Ateliers Pratiques) |
| `finality_id` | INTEGER | YES | NULL | FK to `finality_types` |
| `synopsis` | TEXT | YES | NULL | ~200 word summary |
| `context_note` | TEXT | YES | NULL | Note by jury president (max 150 words) |
| `remarks` | TEXT | YES | NULL | Internal administrative remarks |
| `duration_minutes` | INTEGER | YES | NULL | For audio/video works |
| `duration_pages` | INTEGER | YES | NULL | For written works |
| `file_size_info` | TEXT | YES | NULL | Human-readable size (e.g., "128 pages + 45 minutes") |
| `access_type_id` | INTEGER | YES | NULL | FK to `access_types` |
| `license_id` | INTEGER | YES | NULL | FK to `license_types` |
| `jury_points` | DECIMAL(4,2) | YES | NULL | Grade out of 20 |
| `jury_note_added` | BOOLEAN | NO | 0 | Whether jury added a context note |
| `submitted_at` | DATETIME | YES | NULL | Student submission timestamp |
| `defense_date` | DATETIME | YES | NULL | Date of thesis defense |
| `published_at` | DATETIME | YES | NULL | Public publication timestamp |
| `is_published` | BOOLEAN | NO | 0 | Publication status |
| `baiu_link` | TEXT | YES | NULL | Link to institutional repository (BAIU) |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |
| `updated_at` | DATETIME | NO | CURRENT_TIMESTAMP | Last update time |

**Indexes:**
- `idx_theses_year` ON `year`
- `idx_theses_published` ON `is_published`
- `idx_theses_identifier` ON `identifier`
- `idx_theses_orientation` ON `orientation_id`
- `idx_theses_ap_program` ON `ap_program_id`
- `idx_theses_access_type` ON `access_type_id`

**Constraints:**
- `identifier` must be UNIQUE
- `year` must be > 1950 (implicit validation)
- `jury_points` must be between 0 and 20 (implicit validation)

---

### `authors`
**Purpose:** Store student/author information.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Author full name |
| `email` | TEXT | YES | NULL | Contact email |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |
| `updated_at` | DATETIME | NO | CURRENT_TIMESTAMP | Last update time |

**Indexes:**
- `idx_authors_email` ON `email`

**Notes:**
- Same author can have multiple theses
- Email is optional (privacy)
- No uniqueness constraint on name (same names possible)

---

### `supervisors`
**Purpose:** Store thesis supervisor/promoter information.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Supervisor full name |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |
| `updated_at` | DATETIME | NO | CURRENT_TIMESTAMP | Last update time |

**Notes:**
- Reusable across multiple theses
- No email/contact info stored (administrative data)

---

## Lookup Tables

### `orientations`
**Purpose:** Predefined list of artistic orientations.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Orientation name |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Predefined Values:**
1. Arts Numériques
2. Dessin
3. Cinéma d'animation
4. Installation-Performance
5. Peinture
6. Photographie
7. Sculpture
8. Vidéographie
9. Graphisme
10. Typographie
11. Design Numérique
12. Illustration
13. Bande-Dessinée
14. Sérigraphie
15. Gravure

**Constraints:**
- `name` must be UNIQUE

---

### `ap_programs`
**Purpose:** Practical workshops programs (Ateliers Pratiques).

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Program full name |
| `code` | TEXT | YES | NULL | Short code/acronym |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Predefined Values:**
1. Narration Spéculative (no code)
2. Design et Politique du Multiple (DPM)
3. Atelier Pratiques Situées (APS)
4. Lieux, Interdisciplinarités, Écologie, Nécessité, Systèmes (LIENS)

**Constraints:**
- `name` must be UNIQUE

---

### `finality_types`
**Purpose:** Master degree finality types.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Finality type name |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Predefined Values:**
1. Approfondi (Research-focused)
2. Enseignement (Teaching)
3. Spécialisé (Specialized)

**Constraints:**
- `name` must be UNIQUE

---

### `languages`
**Purpose:** Languages used in thesis.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Language name |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Predefined Values:**
1. Français
2. Anglais

**Notes:**
- Expandable if needed (Dutch, etc.)
- Thesis can be multilingual (junction table)

**Constraints:**
- `name` must be UNIQUE

---

### `format_types`
**Purpose:** Physical/digital format types.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Format type name |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Predefined Values:**
1. Site web
2. Audio
3. Vidéo
4. Performance
5. Objet éditorial (printed matter)
6. Installation
7. Autre (other)

**Notes:**
- Multiple formats per thesis allowed
- "Autre" for edge cases

**Constraints:**
- `name` must be UNIQUE

---

### `access_types`
**Purpose:** Define thesis accessibility levels.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | Access type name |
| `description` | TEXT | YES | NULL | Detailed description |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Predefined Values:**

| ID | Name | Description |
|----|------|-------------|
| 1 | Libre | Full access online and in library |
| 2 | Interne | Physical access only; descriptive note online |
| 3 | Interdit | No access; descriptive note online only |

**Constraints:**
- `name` must be UNIQUE

---

### `license_types`
**Purpose:** Creative Commons and other license types.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `name` | TEXT | NO | - | License name (e.g., "CC BY-SA 4.0") |
| `description` | TEXT | YES | NULL | License description |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Expected Values:**
- CC BY 4.0
- CC BY-SA 4.0
- CC BY-NC 4.0
- CC BY-NC-SA 4.0
- CC0 1.0
- All Rights Reserved
- Custom (text description)

**Constraints:**
- `name` must be UNIQUE

---

### `keywords`
**Purpose:** Expandable keyword/tag list.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `keyword` | TEXT | NO | - | Keyword/tag text |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |

**Notes:**
- Keywords are case-insensitive (normalized to lowercase)
- Maximum 10 keywords per thesis (enforced in application)
- Auto-created when first used
- Can be reused across theses

**Constraints:**
- `keyword` must be UNIQUE

---

## Junction Tables

### `thesis_authors`
**Purpose:** Many-to-many relationship between theses and authors.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `thesis_id` | INTEGER | NO | - | FK to `theses.id` |
| `author_id` | INTEGER | NO | - | FK to `authors.id` |
| `author_order` | INTEGER | NO | 1 | Display order (1, 2, 3...) |

**Primary Key:** (`thesis_id`, `author_id`)

**Cascade Rules:**
- ON DELETE CASCADE (both FKs)

**Notes:**
- Single author: `author_order = 1`
- Multiple authors: ordered by `author_order`

---

### `thesis_supervisors`
**Purpose:** Many-to-many relationship between theses and supervisors.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `thesis_id` | INTEGER | NO | - | FK to `theses.id` |
| `supervisor_id` | INTEGER | NO | - | FK to `supervisors.id` |
| `supervisor_order` | INTEGER | NO | 1 | Display order |

**Primary Key:** (`thesis_id`, `supervisor_id`)

**Cascade Rules:**
- ON DELETE CASCADE (both FKs)

---

### `thesis_languages`
**Purpose:** Many-to-many relationship between theses and languages.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `thesis_id` | INTEGER | NO | - | FK to `theses.id` |
| `language_id` | INTEGER | NO | - | FK to `languages.id` |

**Primary Key:** (`thesis_id`, `language_id`)

**Cascade Rules:**
- ON DELETE CASCADE (both FKs)

---

### `thesis_formats`
**Purpose:** Many-to-many relationship between theses and format types.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `thesis_id` | INTEGER | NO | - | FK to `theses.id` |
| `format_id` | INTEGER | NO | - | FK to `format_types.id` |

**Primary Key:** (`thesis_id`, `format_id`)

**Cascade Rules:**
- ON DELETE CASCADE (both FKs)

---

### `thesis_keywords`
**Purpose:** Many-to-many relationship between theses and keywords.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `thesis_id` | INTEGER | NO | - | FK to `theses.id` |
| `keyword_id` | INTEGER | NO | - | FK to `keywords.id` |

**Primary Key:** (`thesis_id`, `keyword_id`)

**Indexes:**
- `idx_thesis_keywords_thesis` ON `thesis_id`
- `idx_thesis_keywords_keyword` ON `keyword_id`

**Cascade Rules:**
- ON DELETE CASCADE (both FKs)

**Business Rules:**
- Maximum 10 keywords per thesis (enforced in application layer)

---

## Support Tables

### `thesis_files`
**Purpose:** Store file attachments for theses.

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `thesis_id` | INTEGER | NO | - | FK to `theses.id` |
| `file_type` | TEXT | NO | - | Type: 'main', 'annex', 'written_part', 'other' |
| `file_path` | TEXT | NO | - | Relative path to file |
| `file_name` | TEXT | NO | - | Original filename |
| `file_size` | INTEGER | YES | NULL | Size in bytes |
| `mime_type` | TEXT | YES | NULL | MIME type (e.g., 'application/pdf') |
| `description` | TEXT | YES | NULL | File description |
| `uploaded_at` | DATETIME | NO | CURRENT_TIMESTAMP | Upload timestamp |

**Cascade Rules:**
- ON DELETE CASCADE on `thesis_id`

**File Types:**
- **main**: Primary thesis document (PDF, HTML, etc.)
- **annex**: Supplementary materials
- **written_part**: Written component of practice-based thesis
- **other**: Additional files

**Notes:**
- Files stored in `/var/www/html/formulaire/data/theses/`
- Cover images stored in `/var/www/html/formulaire/data/covers/`

---

### `pages`
**Purpose:** Static content management (About, Licenses, Contact, etc.).

| Column | Type | Null | Default | Description |
|--------|------|------|---------|-------------|
| `id` | INTEGER | NO | AUTOINCREMENT | Primary key |
| `slug` | TEXT | NO | - | URL-friendly identifier |
| `title` | TEXT | NO | - | Page title |
| `content` | TEXT | YES | NULL | Page content (Markdown/HTML) |
| `is_published` | BOOLEAN | NO | 1 | Publish status |
| `created_at` | DATETIME | NO | CURRENT_TIMESTAMP | Record creation time |
| `updated_at` | DATETIME | NO | CURRENT_TIMESTAMP | Last update time |

**Predefined Pages:**
- `charte` - Site charter/policy
- `about` - About page
- `licenses` - License information
- `contact` - Contact page

**Constraints:**
- `slug` must be UNIQUE

---

## Views

### `v_theses_full`
**Purpose:** Complete thesis information with all relationships joined.

**Columns:**
- All columns from `theses`
- `orientation` (TEXT) - Orientation name
- `ap_program` (TEXT) - AP program name
- `finality_type` (TEXT) - Finality type name
- `access_type` (TEXT) - Access type name
- `license_type` (TEXT) - License name
- `authors` (TEXT) - Comma-separated author names
- `supervisors` (TEXT) - Comma-separated supervisor names
- `languages` (TEXT) - Comma-separated language names
- `formats` (TEXT) - Comma-separated format names
- `keywords` (TEXT) - Comma-separated keywords

**Usage:**
```sql
SELECT * FROM v_theses_full WHERE id = 123;
```

**Notes:**
- Uses `GROUP_CONCAT` for many-to-many relationships
- Results are comma-delimited strings
- May need post-processing for proper arrays

---

### `v_theses_public`
**Purpose:** Published theses only (for public website).

**Definition:**
```sql
SELECT * FROM v_theses_full WHERE is_published = 1;
```

**Usage:**
```sql
SELECT * FROM v_theses_public ORDER BY year DESC, title;
```

---

## Indexes

### Performance Indexes

| Index Name | Table | Columns | Purpose |
|------------|-------|---------|---------|
| `idx_theses_year` | `theses` | `year` | Filter by year |
| `idx_theses_published` | `theses` | `is_published` | Public/private filtering |
| `idx_theses_identifier` | `theses` | `identifier` | Unique lookup |
| `idx_theses_orientation` | `theses` | `orientation_id` | Filter by orientation |
| `idx_theses_ap_program` | `theses` | `ap_program_id` | Filter by AP program |
| `idx_theses_access_type` | `theses` | `access_type_id` | Access control |
| `idx_authors_email` | `authors` | `email` | Author lookup |
| `idx_thesis_authors_thesis` | `thesis_authors` | `thesis_id` | Join optimization |
| `idx_thesis_authors_author` | `thesis_authors` | `author_id` | Join optimization |
| `idx_thesis_keywords_thesis` | `thesis_keywords` | `thesis_id` | Join optimization |
| `idx_thesis_keywords_keyword` | `thesis_keywords` | `keyword_id` | Keyword search |

---

## Triggers

### Timestamp Update Triggers

**`update_theses_timestamp`**
```sql
AFTER UPDATE ON theses
UPDATE theses SET updated_at = CURRENT_TIMESTAMP WHERE id = NEW.id;
```

**`update_authors_timestamp`**
```sql
AFTER UPDATE ON authors
UPDATE authors SET updated_at = CURRENT_TIMESTAMP WHERE id = NEW.id;
```

**`update_supervisors_timestamp`**
```sql
AFTER UPDATE ON supervisors
UPDATE supervisors SET updated_at = CURRENT_TIMESTAMP WHERE id = NEW.id;
```

**`update_pages_timestamp`**
```sql
AFTER UPDATE ON pages
UPDATE pages SET updated_at = CURRENT_TIMESTAMP WHERE id = NEW.id;
```

---

## Data Types Reference

### SQLite Data Types Used

| Type | SQLite Affinity | Description | Example Values |
|------|----------------|-------------|----------------|
| `INTEGER` | INTEGER | Signed integer | 1, 42, 2025 |
| `TEXT` | TEXT | Variable-length text | "Title", "Name" |
| `BOOLEAN` | INTEGER | 0 or 1 | 0 (false), 1 (true) |
| `DATETIME` | TEXT | ISO8601 timestamp | "2025-02-05 12:00:00" |
| `DECIMAL(4,2)` | REAL | Decimal number | 15.50, 18.75 |

### Boolean Convention
- `FALSE` = 0
- `TRUE` = 1
- NULL = undefined/not set

---

## Business Rules

### Thesis Submission Workflow

1. **Draft Creation** (`is_published = 0`)
   - Student creates initial entry
   - Required fields: title, year, at least one author

2. **Complete Metadata**
   - Add orientation, AP program, finality
   - Upload files
   - Add keywords (max 10)
   - Set languages, formats

3. **Submission** (`submitted_at` set)
   - Student marks as ready for review
   - Email notification to administrators

4. **Defense** (`defense_date` set)
   - After thesis defense
   - Jury adds grade (`jury_points`)
   - Optional context note by jury president

5. **Publication** (`is_published = 1`, `published_at` set)
   - Administrator approves
   - Appears on public website
   - Respects `access_type` rules

### Data Validation Rules

**Required Fields (for publication):**
- `title`
- `year`
- At least one author (via `thesis_authors`)
- `orientation_id`
- `access_type_id`

**Optional but Recommended:**
- `synopsis` (~200 words)
- `keywords` (3-10 recommended)
- At least one file attachment
- `license_id`

**Constraints:**
- `year`: Must be ≥ 1950
- `jury_points`: 0.00 to 20.00
- `keywords`: Maximum 10 per thesis
- `author_order`: Must be sequential (1, 2, 3...)
- `identifier`: Unique across all theses

### Access Control Rules

| Access Type | Public View | Library Access | File Download |
|-------------|-------------|----------------|---------------|
| **Libre** | Full metadata + abstract | Yes | Yes |
| **Interne** | Metadata + descriptive note | Physical only | No |
| **Interdit** | Metadata + descriptive note | No | No |

---

## Sample Queries

### Common Queries

**Get all published theses from 2025:**
```sql
SELECT * FROM v_theses_public 
WHERE year = 2025 
ORDER BY title;
```

**Find theses by author name:**
```sql
SELECT t.* FROM theses t
JOIN thesis_authors ta ON t.id = ta.thesis_id
JOIN authors a ON ta.author_id = a.id
WHERE a.name LIKE '%Dupont%'
AND t.is_published = 1;
```

**Get thesis with all relationships:**
```sql
SELECT * FROM v_theses_full WHERE id = 42;
```

**List theses by orientation:**
```sql
SELECT t.title, t.year, o.name as orientation
FROM theses t
JOIN orientations o ON t.orientation_id = o.id
WHERE o.name = 'Arts Numériques'
AND t.is_published = 1
ORDER BY t.year DESC;
```

**Full-text search in titles and synopses:**
```sql
SELECT * FROM v_theses_public
WHERE title LIKE '%design%'
   OR synopsis LIKE '%design%'
ORDER BY year DESC;
```

**Get theses by keyword:**
```sql
SELECT DISTINCT t.* FROM theses t
JOIN thesis_keywords tk ON t.id = tk.thesis_id
JOIN keywords k ON tk.keyword_id = k.id
WHERE k.keyword = 'écologie'
AND t.is_published = 1;
```

**Count theses per year:**
```sql
SELECT year, COUNT(*) as count
FROM theses
WHERE is_published = 1
GROUP BY year
ORDER BY year DESC;
```

**Get theses with files:**
```sql
SELECT t.title, tf.file_name, tf.file_type
FROM theses t
JOIN thesis_files tf ON t.id = tf.thesis_id
WHERE t.is_published = 1
ORDER BY t.title;
```

**Find theses without keywords:**
```sql
SELECT t.* FROM theses t
LEFT JOIN thesis_keywords tk ON t.id = tk.thesis_id
WHERE tk.thesis_id IS NULL
AND t.is_published = 1;
```

### Administrative Queries

**Recently submitted theses (pending review):**
```sql
SELECT title, submitted_at 
FROM theses 
WHERE submitted_at IS NOT NULL
AND is_published = 0
ORDER BY submitted_at DESC;
```

**Theses missing required metadata:**
```sql
SELECT id, title, year
FROM theses
WHERE (orientation_id IS NULL
   OR access_type_id IS NULL
   OR id NOT IN (SELECT thesis_id FROM thesis_authors))
AND is_published = 0;
```

**Most used keywords:**
```sql
SELECT k.keyword, COUNT(*) as usage_count
FROM keywords k
JOIN thesis_keywords tk ON k.id = tk.keyword_id
GROUP BY k.keyword
ORDER BY usage_count DESC
LIMIT 20;
```

**Theses by supervisor:**
```sql
SELECT s.name as supervisor, COUNT(*) as thesis_count
FROM supervisors s
JOIN thesis_supervisors ts ON s.id = ts.supervisor_id
JOIN theses t ON ts.thesis_id = t.id
WHERE t.is_published = 1
GROUP BY s.name
ORDER BY thesis_count DESC;
```

---

## Making Schema Changes

### How to Request Changes

When requesting schema changes, please specify:

1. **What needs to change**
   - Table name
   - Column name(s)
   - Relationship

2. **Type of change**
   - Add new table
   - Add new column
   - Modify existing column
   - Remove column/table
   - Change relationship

3. **Why it's needed**
   - Use case
   - Business requirement
   - Performance issue

4. **Example data**
   - Sample values
   - Expected format

### Example Change Request

```
**Change Request:** Add support for thesis awards/distinctions

**Type:** Add new table + relationship

**Reason:** Need to track prizes and awards given to theses 
(e.g., "Best TFE 2025", "Jury Prize")

**Proposed Structure:**
- Table: `awards`
  - id (INT, PK)
  - name (TEXT) - Award name
  - description (TEXT) - Award description
  - year (INT) - Year established
  
- Table: `thesis_awards`
  - thesis_id (INT, FK)
  - award_id (INT, FK)
  - awarded_date (DATETIME)

**Example Data:**
- "Prix du Jury 2025"
- "Meilleur TFE Arts Numériques"
- "Prix de l'Innovation"
```

---

## Version History

| Version | Date | Changes |
|---------|------|---------|
| 1.0 | 2026-02-05 | Initial specification document |

---

**For questions or change requests, reference this document and provide:**
- Section name
- Table/column affected
- Desired outcome
- Example use case