| SAS/ACCESS Interface to ADABAS Software |
When you define a view descriptor, you can also include a SORT clause to specify
data order. You can reference only the data fields selected for the view
descriptor, and the data fields must be descriptors; that is, they must have
indexes. Without a SORT clause or a SAS BY statement, the data order is determined
by ADABAS.
A SAS BY statement automatically issues a SORT clause
to ADABAS. If a view descriptor already
contains a SORT clause, the BY statement overrides the sort for that program.
An exception is when the SAS procedure includes the NOTSORTED option. Then,
the SAS BY statement is ignored, and the view descriptor SORT clause is used;
a message is written to the log when NOTSORTED causes a SAS BY statement to
be ignored.
The syntax for the SORT clause
is
SUBSET SORT field-name <,field-name> <,field-name> <option>
The elements of the
SORT clause are described below.
- field-name
- is the name of an ADABAS data
field or its corresponding SAS variable name to sort by. The data field must
be an ADABAS descriptor; that is, it
must be a key data field. You can use the data field's ADABAS field
name or its DDM name.
You can specify up to three data fields; optionally,
you can separate them with commas. If you specify more than one field name,
the values are ordered by the first named field, then the second, and so on.
- option
- is one of the following, which applies to
all specified field names. That is, you cannot specify an option for one field
name and a different option for another field name.
<ASCENDING|ASCENDISN|DESCENDING>
- ASCENDING
- indicates the sort is to be in ascending
order (low-to-high). For example, A, B, C, D or 1, 2, 3 4. The default is
ASCENDING.
- ASCENDISN
- indicates the sort is to be in ascending
ISN (internal sequence number) order. Each logical record in an ADABAS file
has an assigned ISN for identification. If you specify ASCENDISN, you cannot
specify a data field name.
- DESCENDING
- indicates the sort is to be in descending
order (high-to-low). For example, Z, Y, X, W or 9, 8, 7 6.
The following SORT clause causes
the
ADABAS values
to be presented in ascending order. Based on the data fields included in
the VLIB.USACUST view descriptor, the logical records are presented first
by the values in the data field CUSTOMER, then by the values in data field
ZIPCODE, and then by the values in the data field FIRSTORDERDATE.
subset sort customer, zipcode, firstorderdate
The following SORT clause causes logical records that
are accessed by the VLIB.CUSPHON view descriptor to be presented in descending
order based on the values in the NAME data field:
subset sort name descending
Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
