For more information about BY-Group processing, see Chapter 22, 'BY-Group Processing in the DATA Step,' on page 375.
For information about how to use BY-group processing with SAS procedures, see 'Fundamental Concepts for Using Base SAS Procedures' and individual procedures in Base SAS Procedures Guide .
For information about using BY-group processing to combine information from multiple SAS data sets, see Chapter 23, 'Reading, Combining, and Modifying SAS Data Sets,' on page 387. For even more extensive examples of BY-group processing, see Combining and Modifying SAS Data Sets: Examples .
For information about the BY statement, see Statements in SAS Language Reference: Dictionary .
For information about how to use BY-group processing with other software products, see the SAS documentation for those products.