Defines the groups within the record
|| access descriptor
GROUP= group-name LEVEL=level-number
statement defines the groups within the record. This statement is optional.
See Handling GROUP Keys in Descriptor Files for information
about how to reference
GROUP keys in a view descriptor's WHERE statement.
In the GROUP= statement, you must enter the group
name and level
number. The other arguments are used to further define the group and are not
required. The following list explains each argument that can appear in a GROUP=
- is the name that you want to assign to the
group item in an IMS-DL/I database. This name can be a maximum of 32 characters.
If any special characters or blanks are included in the name, enclose the
entire name in quotation marks. This is a required argument.
- is the two-character numeric level of the
IMS-DL/I item. This level number is similar to the COBOL level number. Groups
have levels greater than 01, and their level numbers are less than the level
numbers of the items within the group. This is a required argument.
- indicates with an Y, N, or a U whether this
item is defined in the DBD as a sequence or key field and whether the key
sequence field is unique. The default setting, N, indicates the field is not
a key sequence field. You must assign one key sequence field per segment
if you plan to use the view descriptors that are created from this access
descriptor to update the IMS-DL/I database. Keys are recommended, but not
required, for all segments except the lowest hierarchical level if the view
descriptors will be used only for data retrieval. When KEY=U, retrieval calls
to IMS will be reduced because the IMS engine will know that there is only
one segment in the database for this key.
- indicates the number of times a repeating
group occurs. This is an optional argument.
- is the search field name defined for the
group item in the DBMS DBD. If you want the IMS-DL/I engine to create SSAs
directly from a WHERE statement or command, you must enter the search field
names. Otherwise, the WHERE statement is passed to the SAS System and all
of the segments in the database that are referenced in the view descriptor
are read. SEARCH= is an optional argument, but it is recommended where applicable.
Note: See Handling GROUP Keys in Descriptor Files for
about searching at the GROUP level. Also see Performance and Efficient View Descriptors for more information about SSAs and WHERE
for important information about searching at the GROUP level.
Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.