When "Where" Matters - "If" Matters? - SAS - Differences between 'WHERE" and "IF" statements

A very nice paper with lots of details and a great summary of the differences between "WHERE" and "IF" statements is given in

http://www2.sas.com/proceedings/sugi31/238-31.pdf.

In one of my application recently i found that I had to use the End of File flag (in set statement - EOF=LAST option; LAST=1 or 0 based on whether the file reached the last record or not);

I had to subset the observations and work on the smaller data set and make use of LAST for decision to execute a bloc of statements.

If we use "IF" the execution will not be correct.

Have to use "WHERE" statement to subset.