> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-premium-islands/addressbase-premium-islands-technical-specification/dataset-metadata/trailer-type-99-record.md).

# Trailer – (Type 99 record)

A structured entry which terminates the file. This includes information on the record counts, and next volume number.

{% hint style="info" %}
A Trailer record is not provided in GML or GPKG
{% endhint %}

## Data type attributes <a href="#data-type-attributes" id="data-type-attributes"></a>

The following page provides details about the attributes included with this data type, their types in the different output formats, and other important metadata about them.

### Record identifier

Identifies the record as a Trailer Record (type 99).

* **Attribute Name**: Not provided (GML), RECORD\_IDENTIFIER (CSV), Not provided (GPKG)
* **Data Type:** Integer
* **Size**: 2
* **Multiplicity**: \[1]

### Next volume name

The sequential number of the next volume in the transfer set. For geographic supply this will always be zero (0). For non-geographic supply zero (0) will denote the last file in the transfer set.

* **Attribute Name**: Not provided (GML), NEXT\_VOLUME\_NAME (CSV), Not provided (GPKG)
* **Data Type:** Integer
* **Size**: 3
* **Multiplicity**: \[1]

### Record count

Count of the number of records in the volume (excluding the header record, metadata and trailer records).

* **Attribute Name**: Not provided (GML), RECORD\_COUNT (CSV), Not provided (GPKG)
* **Data Type:** Integer
* **Size**: 16
* **Multiplicity**: \[1]

### Entry date

The date of data entry.

* **Attribute Name**: Not provided (GML), ENTRY\_DATE (CSV), Not provided (GPKG)
* **Data Type:** Date
* **Multiplicity**: \[1]

### Time stamp

Time of creation in HH:MM:SS format.

* **Attribute Name**: Not provided (GML), TIME\_STAMP (CSV), Not provided (GPKG)
* **Data Type:** Time
* **Multiplicity**: \[1]


---

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