Hands-On SAS for Data Analysis

Altering

Using the ALTER statement, we can drop (delete) columns, modify columns, and add columns. The general form of this statement is as follows:

ALTER TABLE table-name       <DROP column-name-1<, ... column-name-n>>       <MODIFY column-definition-1<, ... column-definition-n>>;      <ADD column-definition-1<, ... column-definition-n>> 

Here, table-name specifies the name of the table in which columns will be added, dropped, or modified.

At least one of the following clauses must be specified:

• DROP specifies one or more column-names for columns to be dropped.
• MODIFY specifies one or more column-definitions for columns to be modified, where column-definition specifies a column to be added or modified, and is formatted as follows: column-name data-type ...