Data dictionary and controlled values

This document defines the current public schema and the controlled values enforced by Python and SQLite.

Identifiers

Prefix	Entity	Example
`EQP`	equipment	`EQP-0001`
`REF`	music reference	`REF-0001`
`SC`	soundchain	`SC-0001`

Identifiers are stable public keys. They do not encode private purchase or location information.

`equipment`

Primary key: equipment_id

Controlled values:

Column	Allowed values
`category`	`instrument`, `effect`, `amplification`, `recording_hardware`, `midi_controller`, `software`, `power_utility`
`status_public`	`available`, `planned`, `reference`
`is_hardware`	`true`, `false`
`is_software`	`true`, `false`
`analog_digital`	`analog`, `digital`, `hybrid`, `not_applicable`
`mono_stereo`	`mono`, `stereo`, `both`, `not_applicable`
`data_quality_status`	`sample`, `verified`, `needs_verification`
`privacy_level`	`public_sample`

Exactly one of is_hardware and is_software must be true.

`music_references`

Primary key: reference_id

Column	Allowed values
`importance_public`	`core`, `context`
`reference_role`	`playing_reference`, `sound_design_reference`, `songwriting_reference`, `rhythm_reference`, `production_reference`
`data_quality_status`	`sample`, `verified`, `needs_verification`
`privacy_level`	`public_sample`

`soundchains`

Primary key: soundchain_id

Column	Allowed values
`workflow_type`	`guitar_signal_chain`, `recording_workflow`
`complexity_level`	`basic`, `intermediate`, `advanced`
`status_public`	`draft_public_sample`, `verified_public_sample`
`privacy_level`	`public_sample`

Foreign keys:

primary_reference_id -> music_references.reference_id
primary_instrument_id -> equipment.equipment_id
output_equipment_id -> equipment.equipment_id

`soundchain_equipment`

Primary key: soundchain_id + position_in_chain

Column	Allowed values
`required_or_optional`	`required`, `optional`, `swap_candidate`
`sequence_group`	`input`, `input_output`, `gain_stage`, `modulation`, `midi`, `software`, `output`

position_in_chain must be a positive integer and unique within each soundchain.

Public-data rules

Public CSV files may contain only reviewed sample fields. The workflow rejects selected forbidden column names, sensitive terms, currency-like values, serial-like values and any privacy classification other than public_sample.

Automated checks reduce accidental exposure but do not replace human review.