CFLD segment type format

The IMS catalog CFLD segment type contains information about a field in a particular segment type format case.

Each instance of the CFLD segment describes a field for one case in a segment type format. The information in a CFLD segment instance is valid for a user database segment only if that segment is mapped with the mapping case defined in the parent CASE segment instance.
Segment name
CFLD
Parent name
CASE
Sequence field
FIELDSEQ
Segment length
904 bytes
Table 1. CFLD segment type format
Offset (bytes) Length (bytes) Data type Field name Description Unique key field
1 2 X LEN Length of this segment  
3 2 X CTL Control field  
5 2 X FIELDSEQ Sequence field, type = U X
  5 2 X SEQNUM Sequence number  
9 8 C IMSNAME The 8-character IMS name of this field  
17 3 C NAMESEQ Indicates if this field is a sequence field  
20 1 C SEQUM Indicates whether this field is a unique sequence field (U) or non-unique (M)  
21 2 X BYTES The length of this field in bytes  
23 2 X START The starting offset of this field from the beginning of the segment, in bytes. If this field contains data, the STARTAFT field is not used.  
25 1 C TYPE Indicates what type of binary data IMS uses to pad empty space in this field:
X
Left-padded, X'00'.
P
Left-padded, X'00'.
C
Right-padded, X'40'.
F
Binary fullword data. Only used for MSDBs.
H
Binary halfword data. Only used for MSDBs.
  
26 15 C FILLER01 Reserved  
41 9 C DATATYPE The external (non-IMS) data type of the field  
50 3 C FILLER02 Reserved  
53 2 X PRECISN The precision of a field with a decimal data type  
55 2 X SCALE The scale of a field with a decimal data type  
57 4 X MINOCCURS The minimum number of elements in a DATATYPE=ARRAY field  
61 4 X MAXOCCURS The maximum number of elements in a DATATYPE=ARRAY field  
65 4 X MAXBYTES The maximum number of bytes in a DATATYPE=ARRAY field or in a DATATYPE=STRUCT field that contains an array  
69 4 X RELSTART The relative starting position of the field in bytes  
73 128 C NAME The external alias name of this field  
201 128 C PARENT The external alias name of another field that this field is nested under  
329 128 C REDEFINE The external alias name of another field that this field can be redefined as. The field defined by this instance of the CFLD segment type and the field with the name specified in the REDEFINE field can be processed with a REDEFINES statement in a COBOL application.  
457 128 C DEPENDON The mapping selector field that the field defined by this instance of the CFLD segment type depends on  
585 128 C CASENAME The name of the mapping case that this field belongs to  
713 128 C STARTAFT The external alias name of the field that directly precedes this field in the segment. If this field contains data, the START field does not.  
841 64 C FILLER03 Reserved