The ACCESS procedure enables you to create access descriptors,
which are SAS files of member type ACCESS. They describe data that
is stored in a DBMS in a format that SAS can understand. Access descriptors
enable you to create
SAS/ACCESS views, called view descriptors. View
descriptors are files of member type VIEW that function in the same
way as SAS views that are created with PROC SQL, as described in
Embedding a SAS/ACCESS LIBNAME Statement in a PROC SQL View and
SQL Procedure Pass-Through Facility.
Note: If a dynamic LIBNAME engine
is available for your DBMS, it is recommended that you use the
SAS/ACCESS
LIBNAME statement to access your DBMS data instead of access descriptors
and view descriptors. However, descriptors continue to work in SAS
software if they were available for your DBMS in SAS 6. Some new SAS
features, such as long variable names, are not supported when you
use descriptors.
The following example
creates an access descriptor and a view descriptor in the same PROC
step to retrieve data from a DB2 table:
libname adlib 'SAS-library';
libname vlib 'SAS -library';
proc access dbms=db2;
create adlib.order.access;
table=sasdemo.orders;
assign=no;
list all;
create vlib.custord.view;
select ordernum stocknum shipto;
format ordernum 5.
stocknum 4.;
run;
proc print data=vlib.custord;
run;
When you want to use
access descriptors and view descriptors, both types of descriptors
must be created before you can retrieve your DBMS data. The first
step, creating the access descriptor, enables SAS to store information
about the specific DBMS table that you want to query.
After you have created
the access descriptor, the second step is to create one or more view
descriptors to retrieve some or all of the DBMS data described by
the access descriptor. In the view descriptor, you select variables
and apply formats to manipulate the data for viewing, printing, or
storing in SAS. You use only the view descriptors, and not the access
descriptors, in your SAS programs.
The interface view engine
enables you to reference your SAS view with a two-level SAS name in
a DATA or PROC step, such as the PROC PRINT step in the example.
See
SAS Views for more information about SAS views. See the
SAS/ACCESS
documentation for your DBMS for more detailed information about creating
and using access descriptors and
SAS/ACCESS views.