It does not?
The header surely does not contain the record data, just magic, record and field count, record and string block size.
The file contains a header, the records and the string block, with the header given sizes each.
From the DBC point of view, the structure of the data is irrelevant and a byte blob of record_size * record_count. As you noticed, the LoghtIntBand page then explains the structure inside each record.
In the string Block section there is also code that gives an example of navigating the entire file.