The final section of the XFD is the field section. This is the longest section of the file, because it describes all of the fields contained in the data file.
The file begins with a line describing the number of elementary fields defined for inclusion in the XFD (four digits), the total number of elementary fields in the file (five digits), the number of group and elementary fields listed in the FD (five digits), and the total number of group and elementary fields listed in the FD (five digits).
These last two items — the number and total number of group and elementary fields — may be different if the FD contains an OCCURS clause. Although the total number is increased by the number of times the item OCCURS, the item still has only one listing in the field section of the XFD. Total number is also affected by redefines, group items, and multiple FD descriptions, but it excludes filler fields.
Following the summary line, the field section contains a line for each field definition, listing:
Type Values | Description |
---|---|
0 | Numeric edited |
1 | Unsigned numeric |
2 | Signed numeric (trailing separate) |
3 | Signed numeric (training combined) |
4 | Signed numeric (leading separate) |
5 | Signed numeric (leading combined) |
6 | Signed computational |
7 | Unsigned computational |
8 | Positive packed-decimal |
9 | Signed packed-decimal |
10 | Computational-6 |
11 | Signed binary |
12 | Unsigned binary |
13 | Signed native-order binary |
14 | Unsigned native-order binary |
16 | Alphanumeric |
17 | Alphanumeric (justified) |
18 | Alphabetic |
19 | Alphabetic (justified) |
20 | Alphanumeric edited |
22 | Group |
23 | Float or double |
24 | National |
25 | National (justified) |
26 | National edited |
27 | Wide |
28 | Wide (justified) |
29 | Wide edited |
"000" | no user type |
"001" | date fields |
"002" | binary fields |
"003" | variable-length character |
When a field uses the OCCURS phrase, two special entries appear in the list of field definitions. These entries are designated by offsets of 90001 and 90002. The START-OCCURS entry is defined as follows:
90001,num-occurs,size,START-OCCURS
The END-OCCURS entry is defined as follows:
90002,END-OCCURS
The fields contained in the OCCURS clause are listed between these markers using normal field notation.
Fields that are not defined for actual use but that occur in the FD are indicated by the special condition marker 999.
A simple text field section would appear as follows:
# [Field Section] 0010,00010,00011,00011 0000000000,0000000197,16,0000000197,+00,000,999,01,CLIENT-RECORD 0000000000,0000000005,01,0000000005,+00,000,000,05,CL-CLIENT-ID 0000000005,0000000015,16,0000000015,+00,000,000,05,CL-FIRST-NAME 0000000020,0000000015,16,0000000015,+00,000,000,05,CL-LAST-NAME 0000000035,0000000040,16,0000000040,+00,000,000,05,CL-STREET-ADDR 0000000075,0000000030,16,0000000030,+00,000,000,05,CL-CITY 0000000105,0000000020,16,0000000020,+00,000,000,05,CL-STATE-PROV 0000000125,0000000006,16,0000000006,+00,000,000,05,CL-POST-CODE 0000000131,0000000013,16,0000000013,+00,000,000,05,CL-COUNTRY 0000000144,0000000013,16,0000000013,+00,000,000,05,CL-TEL 0000000157,0000000040,16,0000000040,+00,000,000,05,CL-EMAIL
In an XML-format XFD, the field section description appears as follows:
<xfd:fields xfd:elementary-items="10" xfd:elementary-items-with-occurs="10" xfd:total-items="11" xfd:total-items-with-occurs="11"> <xfd:field xfd:field-offset="0" xfd:field-bytes="197" xfd:field-type="16" xfd:field-length="197" xfd:field-scale="0" xfd:field-user-flags="0" xfd:field-condition="999" xfd:field-level="1" xfd:field-name="CLIENT-RECORD" /> <xfd:field xfd:field-offset="0" xfd:field-bytes="5" xfd:field-type="1" xfd:field-length="5" xfd:field-scale="0" xfd:field-user-flags="0" xfd:field-condition="0" xfd:field-level="5" xfd:field-name="CL-CLIENT-ID" /> . . . </xfd:fields>