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Different types of SAS files serve different
functions. There
are four different types of SAS files.
-
Data sets
- consist of descriptor information and data
values organized as a table of rows and columns that can be processed by one
of the engines. The descriptor information includes data set type, data set
label, the names and labels of the columns in the data set, and so on. A
SAS data set can also include indexes for one or more
columns.
SAS data sets are implemented in two forms:
The default engine processes the data set as if the
data file or data view and the indexes were a single entity.
For more information, see SAS Data Files (Member Type DATA) and
SAS Data Views (Member Type VIEW).
-
Catalogs
- are a special type of SAS file that can
contain multiple entries. Many different types of entries can be kept in
the same SAS catalog. For example, catalogs can contain entries created by SAS/AF and SAS/FSP software,
windowing applications, key definitions, SAS/GRAPH graphs,
and so on.
-
Stored program files
- are compiled DATA steps generated by the
Stored Program Facility. For details on the Stored Program Facility, see
SAS Language Reference: Dictionary.
-
Access descriptor files
- describe the data formatted by other software
products such as the ORACLE or the SYBASE database management systems. Descriptor
files created by the ACCESS procedure in SAS/ACCESS software have the SAS
member type of ACCESS.
The
SAS data file is probably the most frequently used type of SAS file. SAS data
files are created in the DATA step and by some SAS procedures. There are two
types of data files:
A SAS data view contains only the information
needed to derive the data values and the descriptor information. Depending
on how the SAS data view is created, the actual data can be in other SAS data
sets or in other vendors' files.
Views can be of two kinds:
Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.