Introduction to SAS/Library

A SAS data library is a structured storage location within the SAS software environment where datasets are stored and organized. Each Library is assigned a unique name and can be associated with a directory on your file system or a database management system. SAS datasets, which contain structured data and metadata, are stored within these libraries.

SAS libraries are the gateway to access, manage, and analyze data using SAS procedures and programming. They can be permanent or temporary, providing flexibility in data storage and often integrating with external data sources, such as databases and spreadsheets. SAS data libraries support data security by allowing access controls and permissions, and they maintain essential metadata about the datasets they contain, including variable attributes and formats.

Now, we shall discuss the importance of the SAS data library in detail.

As discussed above, a SAS data library is a group of SAS files that SAS recognizes as a unit in your operating system. It is crucial to understand that libraries created by SAS during installation are known as a system defined - Work, Sashelp, Sasuser, etc. Moreover, we can also create the libraries per our requirement called User defined. All used defined libraries and any system defined Library other than WORK are permanent.

You can create libraries in two ways:

1. New library window Method

2. Libname statement

Rules for naming a libref:

· It must be eight characters or less

· Must begin with a letter or underscore

· The remaining characters are letters, numbers, or underscores.

We can create SAS libraries using a point-and-click interface:

Click View → Explorer. Click File → New (New Library Window Opens). Enter details for the new Library in the New Library window.

✓ Name: Name of the Library (Libref )

✓ Engine: Default for Independent Library

✓Click the Enable at Startup check box to have the Library created at the start of every SAS session.

✓ Use the browse button to enter the path of the external folder.

✓ Click OK.

We can even create SAS libraries using LIBNAME Statement

The LIBNAME statement creates the library reference, referred to as libref, and an alias for the SAS data library. A connection is established between a libref in SAS and the actual locations of files on your operating system when you complete the LIBNAME statement.

Libname Libref Engine' Path';

Creating a library by using libname statement: Libname YLP' E: \Clinitrial';

Where Libname → is the Keyword

YLP → Library Name (Libref)

E → is the Drive

Clinitrial → is the Folder Name.

Libraries created by libname cannot be enabled, but they are permanent.

WORK is the default library. If you do not include a library reference in the name of the SAS data set, SAS will assume that the libref is WORK. After a SAS session ends, a WORK library is deleted and is no longer accessible for new sessions. It is mentioned with the first qualifier, WORK, or by a one-level name. After a SAS session, a permanent library is never deleted; it remains open and accessible. It is referenced in a two-level name. The name of the first level should be something other than WORK.

Overall, SAS libraries play a crucial role in data management and analysis within the SAS environment. They provide a centralized location for storing and accessing datasets, making it easier for users to work with data and perform advanced analytics tasks. If you want to understand effective method and techniques of importing data into SAS data, you click on the link to learn.