| SAS Companion for the OpenVMS Operating Environment |
In
order to access an individual SAS file in Version 6 of the SAS System, you
had to first assign a libref or an OpenVMS logical name to the SAS data library.
You could then refer to individual SAS files as libref.member
(or logical-name.member),
where member is the filename of the individual
SAS file.
In Version 8, you can still use librefs or logical names
as a convenient way of referring to a SAS data library in SAS programs. However,
you can also fully specify individual SAS files in most SAS statements and
procedures that access SAS files. If portable SAS code is an issue, then using
librefs is the recommended method.
Although
you can use an OpenVMS logical name
to identify a SAS data library to the SAS System, you may want to use a SAS
libref instead for the following reasons:
- You cannot assign an engine nor specify any engine/host
options with the DCL DEFINE command. SAS uses the procedure described in How SAS Assigns an Engine When No Engine Is Specified
to determine which engine to use. However, it is more efficient to specify
an engine explicitly in a LIBNAME statement. Also, the following SAS engines
must be specified in a LIBNAME statement because they are not assigned by
default: XPORT, SPSS, OSIRIS, and REMOTE.
- OpenVMS logical names are not included in the
list that is produced by the LIBNAME LIST statement until after they have
been used as librefs in your SAS session. (See Listing Your Current Librefs.)
Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
