Update README.md

README.md

@@ -36,6 +36,7 @@ The dataset is provided in **Parquet format** and contains the following columns
 |------------------------|-----------------------------|-----------------------------------------------------------------------------|
 | `chunk_id`             | `str`                       | Unique source based identifier of the chunk                                 |
 | `doc_id`               | `str`                       | Document identifier.                                                        |
+| `chunk_xxh64`          | `str`                       | XXH64 hash of the `chunk_text` value.                                       |
 | `types`                | `str`                       | Type(s) of administrative entity.                                           |
 | `name`                 | `str`                       | Name of the organization or service.                                        |
 | `mission_description`  | `str`                       | Description of the entity's mission.                                        |
@@ -75,6 +76,7 @@ The following fields were extracted and/or transformed from the original JSON:
   - `organizational_chart`, `hierarchy`: structural information within the administration.
 - **Other fields**:
   - `opening_hours`: built using a custom function that parses declared time slots into readable strings.
+  - `chunk_xxh64`: is the xxh64 hash of the `chunk_text` value. It is useful to determine if the `chunk_text` value has changed from a version to another.
 
 ### ✂️ 2. Generation of `chunk_text`