SQL programmers have a number of ways to accomplish their objectives, particularly when the goal is to retrieve and work with data. The SELECT statement is an extremely powerful statement in the SQL language. Its syntax can be somewhat complex because of the number of ways that columns, tables, operators, functions, and predicates can be combined into executable statements.
There are several types of operators and functions in PROC SQL: 1) comparison operators, 2) logical operators, 3) arithmetic operators, 4) character string operators, 5) summary functions, and 6) predicates. Operators and functions provide value-added features for PROC SQL programmers. Each will be presented below.