> For the complete documentation index, see [llms.txt](https://docs.fylr.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fylr.io/for-developers/customdata.md).

# Custom Data

Custom Data Types allow the definition of custom types. The data of such a type is stored as JSON by FYLR.

All custom data is stored in its own table in FYLR, each record is stored only once per `_uuid`. The `_uuid` can be provided or will be auto-generated by FYLR based on the data which was sent. If that data changes a new UUID is generated and a new record is stored. The old record is kept in the database as long as it is references by any object (including historical versions).

## Providing UUID

Custom data can contain a `_uuid` at the top level of the data. With such an id FYLR is not generating one.

> Record uniqueness is determined soley on the provided UUID. So sending different data with the same UUID will not update the stored data. To update the stored data, a new UUID must be provided.

## Search

Custom Data Types support search mappings. The search mapping is defined in the `manifest.yml` of the plugin which defines the Custom Data Type, under `custom_types.<type>.mapping`. Each entry maps a subfield of the custom data to a column type:

```yaml
custom_types:
    example:
        mapping:
            title:
                type: text
            identifier:
                type: text_oneline
                skipTerms: true
```

The `type` of a subfield controls how its value is indexed in OpenSearch (for search and facets) and how it is broken into terms for the suggest term tables.

### skipTerms

> Available since FYLR 6.34.0.

Set `skipTerms: true` on a subfield to keep it **out of the suggest term tables** while it stays indexed in OpenSearch. The value remains searchable and usable for facets, but it no longer contributes terms to `/api/suggest`.

This is useful for subfields whose values would otherwise flood the suggest index — for example identifiers or URLs, which are split into many short fragments when broken into terms.

`skipTerms` affects only the term generation of that one subfield; it does not change how the subfield is indexed for search. It is independent of the instance-wide `fylr.debug.skipTerms` setting, which disables term generation for the whole instance.

## Updates

Custom Data Types can be updated by a background service provided by FYLR. This background service collects all expired custom data and asks a script of the plugin to provide any updates on that data as needed. The updates happen periodically and the Custom Data Type can provide an expiration date for each record.