SAS/ACCESS Descriptor Files for ADABAS

SAS/ACCESS software uses SAS/ACCESS descriptor files to establish a connection between SAS and ADABAS. You create these files with the ACCESS procedure.

There are two types of SAS/ACCESS descriptor files: access descriptors and view descriptors.

The following figure illustrates the relationship among ADABAS data, an access descriptor, and view descriptors.

Access descriptor files are of member type ACCESS. Each access descriptor holds essential information about the ADABAS data that you want to access, such as the ADABAS file number or NATURAL Data Definition Module (DDM) name, the data field names, and their data types. It also contains corresponding information related to SAS, such as the SAS variable names, formats, and informats.

An access descriptor can describe only one ADABAS file or DDM. That is, you cannot join two ADABAS files or DDMs with a single access descriptor.

View descriptor files are sometimes called views because their member type is VIEW. This document uses the term view descriptor to distinguish them from views that are created by the SAS SQL procedure.

Each view descriptor can define all of the data or a particular subset of the data described by one access descriptor (and therefore one ADABAS file or DDM). For example, you might want to use only three or four possible data fields and only some of the logical records. The view descriptor enables you to select the data fields that you want and, by specifying selection criteria, to select only the specific data that you want. For example, your selection criteria might be that the date of transaction is July 3, 2007, and that customers' names begin with W.

Typically, for each access descriptor, you have several view descriptors, selecting different subsets of data.

You can join data from multiple ADABAS files or NATURAL DDMs with SAS SQL procedure. The SQL procedure can join data from SAS data files, PROC SQL views, and SAS/ACCESS view descriptors into one resulting file. In addition, SAS/ACCESS view descriptors can come from different database management systems. For examples that use the SQL procedure, see Introduction to Using ADABAS Data in SAS Programs and Browsing and Updating ADABAS Data.