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The Difference Between WHERE and IF Statements in SAS

In SAS, the WHERE statement is typically used to subset observations based on certain conditions, while the IF statement is used to conditionally execute data step statements based on evaluation of a Boolean expression.

The key difference lies in their functionality - the WHERE statement filters observations at the input data level before they are read into the program, whereas the IF statement filters observations within the data step during program execution.

Therefore, the WHERE statement is useful for reducing the amount of data being processed and improving performance, while the IF statement is ideal for conditional processing within the data step.

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