A feature validation data set (FVDS) reports on all the data it expects to find in the customer’s holding after the application of the supply. It does not identify what is contained in the supply if the order is not full supply. This enables a customer to validate that the data holding contains the correct set of features after loading the data with which it was supplied. All orders of the OS MasterMap Highways Network products will be supplied with a FVDS.
A FVDS is divided into files on a non-geographic basis, and each FVDS will contain up to 4 million rows in a single volume. Where a file will exceed 4 million rows, a new FVDS volume will be created. The FVDS is a comma-separated value (.csv) file that provides the ID, version date and feature type of every feature that should exist in the current data holding; the fields are separated by a comma. Each row will be terminated by Carriage Return / Line Feed, and where a field has no value in a record, two commas will be placed together in the record (one for the end of the previous field and one for the end of the null field). The FVDS will not contain any header information, but the following table identifies the different columns within the file. Each file is compressed using gzip.
The ID (gml:id) of the OS MasterMap Highways Network feature.
The 'beginLifespanVersion' attribute of the feature. This is the date when this feature came into existence, and it will be formatted as follows: YYYY-MM-DD. For example, 2016-06-12.
A textual description of the feature type that the record refers to.