When you access
ADABAS data through the
SAS/ACCESS interface, the interface view engine
maps the
ADABAS data into
SAS observations.
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Multiple-value field occurrences
are mapped to multiple SAS variables. For example, if the
ADABAS data has a multiple-value field named
JOBTITLE with two occurrences, the resulting SAS variables would be
JOBTITL1 and JOBTITL2.
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Periodic group occurrences are mapped to multiple SAS
observations. For example, if the
ADABAS data has a periodic group field named EDUCATION consisting
of data fields COLLEGE, DEGREE, and YEAR, there would be one observation
for COLLEGE, DEGREE, and YEAR for each periodic group occurrence.
When you create
SAS/ACCESS
descriptor files for
ADABAS data, you need to be aware of how some data fields are affected
by the ACCESS procedure and how you can use them as variables in SAS programs.
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When you create a
SAS/ACCESS descriptor
file for
ADABAS data, the
ACCESS procedure automatically creates a SAS variable named ISN.
This variable gives you access to the ISNs (internal sequence numbers)
for all the
ADABAS logical
records.
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Selecting either a
subdescriptor or a
superdescriptor data field creates
a SAS variable for the data field. The variable can be retrieved
and used in a WHERE clause. However, the variable cannot be updated.
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Selecting a
phonetic descriptor data field creates a SAS variable
for that phonetic descriptor. The values of the data field for which
the phonetic descriptor is defined are retrieved, and the phonetic
descriptor can be used in a WHERE clause. However, this variable cannot
be updated.
If you use a variable
for a phonetic descriptor in a SAS WHERE clause, the interface view
engine must be able to process the entire SAS WHERE clause.
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For a
multiple-value data
field, the ACCESS procedure creates SAS variables that reference individual
occurrences and a SAS variable that references all occurrences to
perform special WHERE clause queries. For example, in the NATURAL
DDM named CUSTOMERS, the BRANCH-OFFICE data field is a multiple-value
data field with four occurrences. The ACCESS procedure creates SAS
variables named BRANCH_1, BRANCH_2, and so on, and a SAS variable
named BR_ANY. For more information and examples, see
Multiple-Value Fields in Selection Criteria.
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For a
periodic group data
field, the ACCESS procedure creates a SAS variable for the occurrence
number within the periodic group. For example, in the NATURAL DDM
named CUSTOMERS, the SIGNATURE-LIST data field is a periodic group
for data fields LIMIT and SIGNATURE. PROC ACCESS creates a SAS variable
named SL_OCCUR for the occurrence numbers. For more information and
examples, see
Periodic Group Fields in Selection Criteria.