SAS 9.4 Language Reference, 6th Edition

The SAS/CONNECT client signs on to the SAS/CONNECT server named REMPC. A

server library is assigned to the client session. The value for SERVER= is the same as

the server session ID that is used in the SIGNON statement.

For more information about SAS/CONNECT, see SAS/CONNECT User’s Guide.

SAS/SHARE Example:

The SAS/SHARE client uses a LIBNAME statement to access a server library via the

existing libref, Sales, which was pre-defined at the SAS/SHARE server for client access.

libname sales server=server1;

For more information about SAS/SHARE, see SAS/SHARE User’s Guide.

Remote Library Access for WebDAV Servers

WebDAV (Web Distributed Authoring and Versioning) is a protocol that enhances the

HTTP protocol. It provides a standard infrastructure for collaborative authoring across

the Internet. WebDAV enables you to edit web documents, stores versions for later

retrieval, and provides a locking mechanism to prevent overwriting. SAS supports the

WebDAV protocol under the UNIX and Windows operating environments.

You use a LIBNAME statement to access WebDAV servers, as shown in the following

example:

libname davdata v9 "http://www.webserver.com/users/mydir/datadir"

webdav user="mydir" pw="12345";

When you access files on a WebDAV server, SAS pulls the file from the server to your

local disk for processing. The files are temporarily stored in the SAS Work directory,

unless you use the LOCALCACHE= option in the LIBNAME statement, which

specifies a different directory for temporary storage. When you finish updating the file,

SAS pushes the file back to the WebDAV server for storage and removes the file from

the local disk.

For more information, see “WHEREUP= Data Set Option” in SAS Data Set Options:

Reference.

Library Concatenation

Definition of Library Concatenation

Concatenation is the logical combining of two or more libraries. Concatenation enables

you to access the SAS data sets in several libraries with one libref.

You can concatenate two or more libraries by specifying their librefs or physical names

in the LIBNAME statement or function.

Physical names must be enclosed in single or double quotation marks in a LIBNAME

statement. Otherwise, SAS looks for a previously assigned libref with the same name.

In the following examples, Summer, Winter, Spring, Fall, and Annual are previously

defined librefs:

libname annual (summer winter spring fall);

libname annual ('SAS-library-1' 'SAS-library-2' 'SAS-library-3');

libname annual ('SAS-library' winter spring fall);

590 Chapter 26 • SAS Libraries

libname total (annual 'SAS-library');

How SAS Concatenates Library Members

When there are members of the same name in more than one library, the first occurrence

of the member is used for input and update processes. Output always goes to the first

library.

This example contains three SAS libraries, and each library contains two SAS data files:

Lib1

Apples and Pears

Lib2

Apples and Oranges

Lib3

Oranges and Plums

The LIBNAME statement concatenates Lib1, Lib2, and Lib3:

libname fruit (lib1 lib2 lib3);

The concatenated library Fruit has the following members:

• Apples

• Pears

• Oranges

• Plums

Note: Output always goes to the first library. For example, the following statement

writes to the first library in the concatenation, Lib1:

data fruit.oranges;

Note that in this example, if the file Apples in Lib1 was different from the file Apples in

Lib2, and if an update to Apples was specified, it is updated only in Lib1 because that is

the first occurrence of the member Apples.

For complete documentation on library concatenation, see the “LIBNAME Statement” in

SAS Global Statements: Reference.

Operating Environment Information

For more information about how specific operating environments handle

concatenation, see the SAS documentation for your operating environment.

Rules for Library Concatenation

After you create a library concatenation, you can specify the libref in any context that

accepts a simple (nonconcatenated) libref. These rules determine how SAS files (that is,

members of SAS libraries) are located among the concatenated libraries:

• If you specify any options or an engine, the options apply only to the libraries that

you specified with the physical name, not to any library that you specified with a

libref.

• When a SAS file is opened for input or update, the concatenated libraries are

searched and the first occurrence of the specified file is used.

Library Concatenation 591