From Xojo Documentation

Read-Only Property (As String )
StringValue = aDatabaseField.NativeValue

Supported for all project types and targets.

Used to get the values of fields in their native encoding. Useful for reading blobs from database fields. Use Value or StringValue to set Blob values in database fields.

Sample Code

Get the native value of a column in a RecordSet:

// rs is a RecordSet with a BLOB column called "FileData"
Dim data As String
data = rs.Field("FileData").NativeValue