# INVALID_UNIQUE_KEY — unique key fields are null or invalid

A composite unique key requires every declared field to be present and non-null. This error is returned when the entity payload is missing a value for at …

<em>cyoda-go version <a href="https://github.com/Cyoda/cyoda-go/releases/tag/v0.8.2">0.8.2</a></em>

# errors.INVALID_UNIQUE_KEY

## NAME

INVALID_UNIQUE_KEY — the engine could not compute a complete composite unique key because one or more required key fields are null or carry an unsupported value type.

## SYNOPSIS

HTTP: `422` `Unprocessable Entity`. Retryable: `no`.

## DESCRIPTION

A composite unique key requires every declared field to be present and non-null. This error is returned when the entity payload is missing a value for at least one key field, or the value cannot be normalized to a valid claim (for example, a NaN or ±Infinity for a numeric key field).

To resolve: ensure every field listed in the model's unique key definition has a valid, non-null value in the submitted entity payload.

## SEE ALSO

- errors
- errors.UNIQUE_VIOLATION
- errors.INVALID_UNIQUE_KEY_DEFINITION

## See also

- [`cyoda help errors`](/help/errors/) — Every error response from the Cyoda REST API carries a structured `errorCode` in the `properties` object. Multiple codes may share the same HTTP status. Programmatic handling keys on `errorCode`, not HTTP status.
- [`cyoda help errors UNIQUE_VIOLATION`](/help/errors/unique_violation/) — The entity payload contains field values that collide with an existing entity's composite unique key. Unlike an optimistic-concurrency CONFLICT (which is retryable), a unique-key violation is a permanent data constraint — retrying the same payload without changing the key field values will produce the same result.
- [`cyoda help errors INVALID_UNIQUE_KEY_DEFINITION`](/help/errors/invalid_unique_key_definition/) — Each unique key on a model must have a non-empty list of field paths, a unique name within the model, and field paths that resolve to existing, non-ambiguous fields in the model schema. This error is returned when a submitted model definition violates one of these structural requirements.

## Raw formats

- [`/help/errors/invalid_unique_key.json`](/help/errors/invalid_unique_key.json) — full descriptor (matches `GET /help/{topic}` envelope)
- [`/help/errors/invalid_unique_key.md`](/help/errors/invalid_unique_key.md) — body only