tabulae-aeriae/documentation/administrative/tabulae-aeriae-data-dictionary.md

# Tabulae Aeriae — Data Dictionary

**Version:** 1.0  
**Date:** March 29, 2026

This document defines every table and field in the Tabulae Aeriae database schema. All tables use PostgreSQL. All timestamps are stored in UTC. All time durations are stored as INTEGER minutes.

---

## Table: `users`

Pilot accounts, authentication credentials, and profile settings.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `username` | VARCHAR(100) | NO | — | Unique login username |
| `email` | VARCHAR(255) | YES | — | Unique email address |
| `password_hash` | TEXT | NO | — | Bcrypt-hashed password |
| `role` | VARCHAR(20) | NO | `'pilot'` | User role: `pilot`, `admin` |
| `tier` | VARCHAR(20) | NO | `'free'` | Feature tier: `free`, `professional` |
| `pilot_cert_num` | VARCHAR(50) | YES | — | FAA pilot certificate number |
| `regulatory_profile` | VARCHAR(10) | NO | `'faa'` | Active regulatory framework: `faa`, `easa`, `both` |
| `auth_provider` | VARCHAR(30) | NO | `'password'` | Auth method: `password`, `google`, `oidc`, `ldap` |
| `external_auth_id` | VARCHAR(255) | YES | — | External provider's user ID (for OAuth/LDAP) |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp (UTC) |
| `updated_at` | TIMESTAMPTZ | NO | `now()` | Last modification timestamp (UTC) |

**Indexes:**
- `users_username_key` — UNIQUE on `username`
- `users_email_key` — UNIQUE on `email`

**Audit:** Tracked (INSERT/UPDATE/DELETE trigger → `audit_log`)

---

## Table: `flights`

Core logbook entries. Each row represents one flight leg or one simulator/training device session. All time fields are stored as INTEGER minutes. All timestamps are UTC.

### Identification

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `user_id` | UUID | NO | — | FK → `users.id`. Owner of this flight record |

### Date, Route, and Block Times

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `flight_date` | DATE | NO | — | Date of flight (UTC date) |
| `departure_airport` | VARCHAR(10) | NO | — | Departure airport code (ICAO or FAA LID). Stored as-entered for historical accuracy |
| `arrival_airport` | VARCHAR(10) | NO | — | Arrival airport code. Stored as-entered for historical accuracy |
| `route` | TEXT | YES | — | Free-text route of flight (intermediate waypoints, airways, etc.) |
| `departure_time` | TIMESTAMPTZ | YES | — | Block out / wheels up time (UTC). NULL if pilot logs duration only |
| `arrival_time` | TIMESTAMPTZ | YES | — | Block in / wheels down time (UTC). NULL if pilot logs duration only |

### Aircraft

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `aircraft_id` | UUID | YES | — | FK → `aircraft.id`. Links to aircraft or simulator record |
| `tail_number` | VARCHAR(20) | NO | — | Aircraft registration or simulator identifier. Denormalized from aircraft record for historical accuracy (registrations change over time) |

### Flight Times (INTEGER minutes)

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `total_time` | INTEGER | NO | `0` | Total flight/session time. Authoritative value — may be auto-derived from departure/arrival times but is always manually overridable |
| `pic_time` | INTEGER | YES | `0` | Pilot-in-command time |
| `sic_time` | INTEGER | YES | `0` | Second-in-command time |
| `solo_time` | INTEGER | YES | `0` | Solo flight time |
| `dual_received` | INTEGER | YES | `0` | Dual instruction received time |
| `dual_given` | INTEGER | YES | `0` | Instruction given time (CFI logging) |
| `cross_country` | INTEGER | YES | `0` | Cross-country time. Pilot's determination per 14 CFR 61.1(b) |
| `night_time` | INTEGER | YES | `0` | Night time (sunset to sunrise definition per 61.51(b)(3)(i)) |

### Instrument

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `actual_instrument` | INTEGER | YES | `0` | Time in actual instrument meteorological conditions |
| `simulated_instrument` | INTEGER | YES | `0` | Simulated instrument time (hood/foggles/view-limiting device) |
| `holds` | SMALLINT | YES | `0` | Number of holding patterns performed |
| `approaches` | JSONB | YES | `'[]'` | Instrument approaches. Array of objects: `[{"type": "ILS", "airport": "KTPA", "runway": "19L", "notes": ""}]`. Type validated against approach enum |

**Approach type enum values:** `ILS`, `LOC`, `LOC-BC`, `VOR`, `VOR/DME`, `NDB`, `RNAV (GPS)`, `RNAV (RNP)`, `LPV`, `LNAV`, `LNAV/VNAV`, `GPS`, `MLS`, `SDF`, `LDA`, `PAR`, `ASR`, `VISUAL`, `CONTACT`

### Takeoffs and Landings

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `day_takeoffs` | SMALLINT | YES | `0` | Day takeoffs (sun above horizon at departure airport at departure time) |
| `night_takeoffs` | SMALLINT | YES | `0` | Night takeoffs (1 hr after sunset to 1 hr before sunrise per 61.57(b) at departure airport) |
| `day_landings` | SMALLINT | YES | `0` | Day landings |
| `night_landings` | SMALLINT | YES | `0` | Night landings (1 hr after sunset to 1 hr before sunrise per 61.57(b) at arrival airport) |
| `day_full_stop` | SMALLINT | YES | `0` | Day full-stop landings (required for tailwheel currency) |
| `night_full_stop` | SMALLINT | YES | `0` | Night full-stop landings (required for night currency per 61.57(b)) |

**Note on day/night classification:** Takeoffs and landings are independently classified as day or night. A single-leg flight may have a day takeoff and a night landing (or vice versa). Auto-suggestion is computed from departure/arrival times and airport solar position, always pilot-overridable.

### Simulator / Training Device

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `simulator_time` | INTEGER | YES | `0` | Time logged in an FFS, FTD, or ATD |
| `sim_type` | VARCHAR(20) | YES | — | Type of device used for this session: `FFS`, `FTD`, `AATD`, `BATD`. NULL for real aircraft flights |
| `ground_training` | INTEGER | YES | `0` | Ground instruction time (minutes) |

### Glider Operations

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `launch_type` | VARCHAR(20) | YES | — | Glider launch method: `aero_tow`, `ground_launch`, `powered_launch`, `self_launch`. NULL for non-glider flights. Required by 8710 for glider time reporting |

### People

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `persons_on_board` | TEXT | YES | — | Free text or crew listing |
| `instructor_name` | VARCHAR(100) | YES | — | Name of instructor (when receiving instruction) |
| `instructor_cert_num` | VARCHAR(50) | YES | — | Instructor's CFI certificate number |

### Remarks

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `remarks` | TEXT | YES | — | Free-text remarks, endorsement references, crew names, etc. |

### EASA Skeleton Fields

These columns are nullable and hidden in the UI when `users.regulatory_profile = 'faa'`. They exist to enable future EASA compliance without destructive schema migrations.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `multi_pilot_time` | INTEGER | YES | — | EASA: multi-pilot operations time (minutes) |
| `co_pilot_time` | INTEGER | YES | — | EASA: co-pilot time (minutes) |
| `spse_time` | INTEGER | YES | — | EASA: single-pilot single-engine time (minutes) |
| `spme_time` | INTEGER | YES | — | EASA: single-pilot multi-engine time (minutes) |
| `pic_name` | VARCHAR(100) | YES | — | EASA: name of PIC (required for all flights under EASA) |
| `function_type` | VARCHAR(20) | YES | — | EASA: pilot function — `PIC`, `co-pilot`, `dual`, `instructor` |

### Custom and Extension Fields

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `custom_fields` | JSONB | YES | `'{}'` | User-defined fields for company, insurance, or personal tracking. Examples: `{"pf": true, "ioe_time": 120, "company_route_id": "ATL-MIA-142"}` |

### Metadata

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp (UTC) |
| `updated_at` | TIMESTAMPTZ | NO | `now()` | Last modification timestamp (UTC) |

**Indexes:**
- `idx_flights_user_date` — on `(user_id, flight_date DESC)`
- `idx_flights_user_aircraft` — on `(user_id, aircraft_id)`

**Audit:** Tracked (INSERT/UPDATE/DELETE trigger → `audit_log`)

---

## Table: `aircraft`

Aircraft and training device records. Simulators and FTDs are stored here alongside real aircraft, distinguished by `is_simulator = TRUE`.

### Identification

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `user_id` | UUID | NO | — | FK → `users.id`. Owner of this aircraft record |
| `tail_number` | VARCHAR(20) | NO | — | Aircraft registration (e.g., `N453FX`) or simulator identifier (e.g., `SIM-GLF4-01`) |

### Aircraft Details

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `type_code` | VARCHAR(10) | YES | — | ICAO type designator (e.g., `C172`, `GLF4`, `B738`) |
| `make_model` | VARCHAR(100) | NO | — | Full make and model (e.g., `Gulfstream G450`, `Cessna 172S Skyhawk SP`) |
| `category_class` | VARCHAR(50) | NO | — | FAA category/class. Values: `ASEL`, `AMEL`, `ASES`, `AMES`, `RH`, `RG`, `GL`, `LTA-B`, `LTA-A`, `PL` |

### Aircraft Attributes

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `is_complex` | BOOLEAN | YES | `FALSE` | Complex aircraft (retractable gear + flaps + controllable prop) |
| `is_high_perf` | BOOLEAN | YES | `FALSE` | High performance (>200 HP) |
| `is_tailwheel` | BOOLEAN | YES | `FALSE` | Conventional landing gear (tailwheel/taildragger) |
| `is_taa` | BOOLEAN | YES | `FALSE` | Technologically Advanced Aircraft (PFD + MFD + 2-axis autopilot) |
| `gear_type` | VARCHAR(20) | YES | — | Landing gear type: `fixed_tri`, `retract`, `conventional`, `float`, `amphibious`, `ski` |
| `engine_type` | VARCHAR(20) | YES | — | Engine type: `piston`, `turboprop`, `jet`, `electric` |
| `num_engines` | SMALLINT | YES | `1` | Number of engines |

### Simulator / Training Device Fields

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `is_simulator` | BOOLEAN | YES | `FALSE` | TRUE for FFS, FTD, ATD devices; FALSE for real aircraft |
| `device_level` | VARCHAR(20) | YES | — | Qualification level: `FFS_A`, `FFS_B`, `FFS_C`, `FFS_D`, `FTD_4`, `FTD_5`, `FTD_6`, `FTD_7`, `AATD`, `BATD`. NULL for real aircraft |
| `device_serial` | VARCHAR(50) | YES | — | Device serial number or regulatory identifier. NULL for real aircraft |
| `device_approval` | VARCHAR(100) | YES | — | FAA approval/qualification number. NULL for real aircraft |

### EASA Skeleton Fields

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `easa_type_designator` | VARCHAR(20) | YES | — | EASA type designator (may differ from ICAO) |
| `sp_mp` | VARCHAR(5) | YES | — | Single-pilot or multi-pilot: `SP`, `MP` |

### Metadata

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp (UTC) |
| `updated_at` | TIMESTAMPTZ | NO | `now()` | Last modification timestamp (UTC) |

**Indexes:**
- UNIQUE on `(user_id, tail_number)`

**Audit:** Tracked (INSERT/UPDATE/DELETE trigger → `audit_log`)

---

## Table: `airports`

Airport reference data. Seeded from OurAirports (`davidmegginson/ourairports-data`). Users may add custom airports.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | SERIAL | NO | auto-increment | Primary key |
| `icao_code` | VARCHAR(4) | YES | — | ICAO airport code (e.g., `KJFK`) |
| `faa_code` | VARCHAR(4) | YES | — | FAA Location Identifier (e.g., `JFK`, `7B2`). For US airports, may differ from ICAO |
| `iata_code` | VARCHAR(3) | YES | — | IATA code (e.g., `JFK`) |
| `name` | VARCHAR(200) | NO | — | Airport name |
| `city` | VARCHAR(100) | YES | — | Primary municipality served |
| `state_region` | VARCHAR(100) | YES | — | State or administrative region |
| `country` | VARCHAR(2) | YES | — | ISO 3166-1 alpha-2 country code |
| `latitude` | DECIMAL(10,7) | YES | — | Latitude in decimal degrees (positive = north) |
| `longitude` | DECIMAL(10,7) | YES | — | Longitude in decimal degrees (positive = east) |
| `elevation_ft` | INTEGER | YES | — | Field elevation MSL in feet |
| `type` | VARCHAR(30) | YES | — | Airport type: `large_airport`, `medium_airport`, `small_airport`, `heliport`, `seaplane_base`, `closed` |
| `is_user_defined` | BOOLEAN | YES | `FALSE` | TRUE for user-added custom airports/strips |
| `user_id` | UUID | YES | — | FK → `users.id`. NULL for system (OurAirports) records |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp |

**Indexes:**
- `idx_airports_icao` — on `icao_code`
- `idx_airports_faa` — on `faa_code`
- `idx_airports_name` — GIN index on `to_tsvector('english', name)` for full-text search

---

## Table: `airport_identifiers`

Maps current and historical airport codes to physical airport records. Enables lookup of retired codes (e.g., 09G → KTEW) while preserving historical accuracy in flight records.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | SERIAL | NO | auto-increment | Primary key |
| `airport_id` | INTEGER | NO | — | FK → `airports.id`. The physical airport this identifier refers to |
| `identifier` | VARCHAR(10) | NO | — | The airport code (e.g., `09G`, `KTEW`, `JFK`) |
| `identifier_type` | VARCHAR(10) | NO | — | Code type: `icao`, `faa`, `iata`, `former` |
| `is_current` | BOOLEAN | YES | `TRUE` | TRUE if this code is currently active for the airport |
| `effective_from` | DATE | YES | — | Date this code became active (NULL if unknown) |
| `effective_to` | DATE | YES | — | Date this code was retired (NULL if currently active) |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp |

**Indexes:**
- UNIQUE on `(identifier, identifier_type)` WHERE `is_current = TRUE`
- `idx_airport_ident_all` — on `identifier` (covers former codes)

**Resolution flow:** User enters airport code → system searches `airport_identifiers` → finds physical airport → resolves lat/long for map display → stores original code in flight record unchanged.

---

## Table: `pilot_qualifications`

Unified table for pilot certificates, ratings, endorsements, and currency events. Each row represents one qualification or one currency event.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `user_id` | UUID | NO | — | FK → `users.id` |
| `qual_type` | VARCHAR(30) | NO | — | Qualification type (see enum below) |
| `certificate_grade` | VARCHAR(30) | YES | — | For `pilot_certificate`: `student`, `private`, `commercial`, `atp`, `atp_restricted` |
| `certificate_number` | VARCHAR(50) | YES | — | FAA certificate number |
| `rating_name` | VARCHAR(100) | YES | — | Rating or endorsement name (e.g., `ASEL`, `AMEL`, `CE-500`, `Instrument Airplane`, `Complex`, `High Performance`, `High Altitude`) |
| `date_earned` | DATE | NO | — | Date the qualification was earned or event occurred |
| `expiry_date` | DATE | YES | — | Expiration date (NULL for non-expiring qualifications) |
| `flight_id` | UUID | YES | — | FK → `flights.id`. Links to the flight where this event occurred (NULL for events not tied to a flight record, e.g., ground-only checkrides, sim-only IPCs) |
| `issuing_authority` | VARCHAR(100) | YES | — | Issuing body (e.g., `FAA`, `EASA`) |
| `instructor_name` | VARCHAR(100) | YES | — | Name of endorsing instructor (for endorsements and currency events) |
| `instructor_cert` | VARCHAR(50) | YES | — | Endorsing instructor's certificate number |
| `examiner_name` | VARCHAR(100) | YES | — | Name of designated examiner (for checkrides, IPCs) |
| `regulation_ref` | VARCHAR(50) | YES | — | Regulatory reference (e.g., `61.31(e)`, `61.56`, `61.57(d)`) |
| `document_ref` | TEXT | YES | — | Reference to scan/photo of supporting document (future: attachment support) |
| `notes` | TEXT | YES | — | Free-text notes |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp |
| `updated_at` | TIMESTAMPTZ | NO | `now()` | Last modification timestamp |

**`qual_type` enum values:**

| Value | Category | Description |
|-------|----------|-------------|
| `pilot_certificate` | Certificate | Pilot certificate (student, private, commercial, ATP) |
| `flight_instructor` | Certificate | CFI, CFII, MEI certificate |
| `ground_instructor` | Certificate | Basic, Advanced, or Instrument ground instructor |
| `type_rating` | Rating | Aircraft type rating (e.g., CE-500, GLF4, B737) |
| `instrument_rating` | Rating | Instrument rating by category |
| `category_class_rating` | Rating | Additional category/class rating |
| `endorsement` | Endorsement | Instructor endorsement (complex, high-perf, high-altitude, tailwheel, etc.) |
| `flight_review` | Currency event | Flight review per 61.56 |
| `ipc` | Currency event | Instrument proficiency check per 61.57(d) |
| `checkride` | Currency event | Practical test (also satisfies flight review) |
| `wings_phase` | Currency event | WINGS Pilot Proficiency Program phase completion |
| `proficiency_check` | Currency event | Part 135/121 proficiency check |
| `135_recurrent` | Currency event | Part 135 recurrent training completion |
| `121_recurrent` | Currency event | Part 121 recurrent training completion |

**Indexes:**
- `idx_qual_user_type` — on `(user_id, qual_type)`
- `idx_qual_user_date` — on `(user_id, date_earned DESC)`

---

## Table: `medical_certificates`

FAA medical certificate records.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `user_id` | UUID | NO | — | FK → `users.id` |
| `class` | SMALLINT | NO | — | Medical class: `1`, `2`, `3` |
| `issue_date` | DATE | NO | — | Date medical was issued |
| `expiry_date` | DATE | NO | — | Calculated expiration date per 14 CFR 61.23 (based on age and class) |
| `examiner_name` | VARCHAR(100) | YES | — | Aviation Medical Examiner (AME) name |
| `notes` | TEXT | YES | — | Free-text notes (restrictions, limitations, BasicMed status, etc.) |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp |

---

## Table: `saved_reports`

User-saved report configurations for one-click report generation.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `user_id` | UUID | NO | — | FK → `users.id` |
| `name` | VARCHAR(100) | NO | — | Report name (e.g., `8710 Application`, `Insurance Renewal`, `Annual Totals`) |
| `description` | TEXT | YES | — | User-provided description of this report |
| `report_type` | VARCHAR(30) | NO | — | Report category: `summary`, `detailed`, `8710`, `medical`, `currency`, `by_aircraft`, `custom` |
| `config` | JSONB | NO | — | Full report configuration: date range, filters, grouping, columns, output format |
| `is_quick_access` | BOOLEAN | YES | `FALSE` | If TRUE, report appears as a dashboard button for one-click access |
| `sort_order` | SMALLINT | YES | `0` | Display order for quick-access buttons |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp |
| `updated_at` | TIMESTAMPTZ | NO | `now()` | Last modification timestamp |

**Config JSONB structure example:**
```json
{
  "date_range": {"type": "rolling", "months": 6},
  "filters": {"category_class": ["AMEL"], "aircraft_type": ["GLF4"]},
  "grouping": "month",
  "columns": ["total_time", "pic_time", "night_time", "actual_instrument", "approaches"],
  "output_format": "screen",
  "rounding": "truncate"
}
```

---

## Table: `currency_rules`

JSON-driven currency rule definitions. System-defined rules (FAA defaults) have `user_id = NULL`. Users can add custom rules for personal minimums or company requirements.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `user_id` | UUID | YES | — | FK → `users.id`. NULL for system-defined rules |
| `name` | VARCHAR(100) | NO | — | Rule display name (e.g., `Night Currency — ASEL`, `IFR Currency`) |
| `regulation_ref` | VARCHAR(50) | YES | — | Regulatory reference (e.g., `61.57(a)`, `61.57(c)`) |
| `rule_config` | JSONB | NO | — | Complete rule configuration (lookback window, requirements, thresholds, grace periods, remediation text) |
| `is_active` | BOOLEAN | YES | `TRUE` | Whether this rule is currently being evaluated |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp |

**See Currency Rules Engine document for complete `rule_config` schema and examples.**

---

## Table: `audit_log`

Append-only changelog capturing all modifications to tracked tables. Populated automatically by PostgreSQL triggers on `flights`, `aircraft`, and `users`.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | BIGSERIAL | NO | auto-increment | Primary key |
| `table_name` | VARCHAR(50) | NO | — | Name of the modified table |
| `record_id` | UUID | NO | — | Primary key of the modified record |
| `action` | VARCHAR(10) | NO | — | Operation type: `INSERT`, `UPDATE`, `DELETE` |
| `old_value` | JSONB | YES | — | Full row before modification (NULL for INSERT) |
| `new_value` | JSONB | YES | — | Full row after modification (NULL for DELETE) |
| `changed_by` | UUID | YES | — | FK → `users.id`. User who made the change. Set via PostgreSQL session variable `app.current_user_id` |
| `changed_at` | TIMESTAMPTZ | NO | `now()` | Timestamp of the change (UTC) |

**Indexes:**
- `idx_audit_record` — on `(table_name, record_id)`
- `idx_audit_time` — on `changed_at`

**Implementation:** PostgreSQL `AFTER INSERT OR UPDATE OR DELETE` trigger on each tracked table calls `audit_trigger_fn()`. The application middleware sets `SET LOCAL app.current_user_id = $1` on each transaction so the trigger can capture the acting user.

---

## Deferred Table: `pilot_status_periods`

**Not included in v1 schema. Designed for paid tier.**

Tracks date-range statuses such as high minimums captain periods.

| Column | Type | Nullable | Default | Description |
|--------|------|----------|---------|-------------|
| `id` | UUID | NO | `gen_random_uuid()` | Primary key |
| `user_id` | UUID | NO | — | FK → `users.id` |
| `status_type` | VARCHAR(50) | NO | — | Status type: `high_mins`, `line_check_required`, `probationary`, etc. |
| `start_date` | DATE | NO | — | Start of status period |
| `end_date` | DATE | YES | — | End of status period (NULL = still active) |
| `notes` | TEXT | YES | — | Free-text notes |
| `created_at` | TIMESTAMPTZ | NO | `now()` | Record creation timestamp |

---

## Foreign Key Reference Map

```
users
  ├── flights.user_id
  ├── aircraft.user_id
  ├── airports.user_id (user-defined airports only)
  ├── pilot_qualifications.user_id
  ├── medical_certificates.user_id
  ├── saved_reports.user_id
  ├── currency_rules.user_id (NULL for system rules)
  └── audit_log.changed_by

aircraft
  └── flights.aircraft_id

flights
  └── pilot_qualifications.flight_id

airports
  └── airport_identifiers.airport_id
```