In fixed-length or fixed-format records, each field starts and
ends at the same place in every record. A data file that contains
data records of equal and constant length might be organized as follows. Figure 1. Sample
file with fixed-length records
aaabbbbcccddddggghhhh
The data file illustrated previously has three records. Each record
has a field of three characters followed by a field of four characters,
so the total record length is seven characters. The file does not
contain any separation between records; delimiters are unnecessary
because all fields have the same length. The VARCHAR data types are
therefore always the fixed maximum size of the field.
When you define a fixed-length format, you specify the length of
each field. The ipload utility calculates the offset
for each field and the total length of the record from the field lengths
that you supply.