Does any of your experts know whether a where statement in data step for subsetting is processed differently from where = dataset option, when there is only one input dataset?
Here is the only quote from SAS help that I found.
"The WHERE statement applies to all input data sets, whereas the WHERE= data set option selects observations only from the data set for which it is specified."
My friend also read from somewhere that a where = option is more efficient as it only brings the qualified observations into PDV, while a where statement will read in all the observations then discard the unqualified data. What he mentioned also sounds like the difference between IF and Where statement for subsetting, so I'm a bit confused.
The WHERE statement and WHERE= data set option are equivalent, for example, when you have only one dataset referenced on the SET statement (or when using a PROC that accepts WHERE filtering, when loading input data into the PDV. I find the WHERE statement easier to code.
Suggested Google advanced search argument, this topic / post:
+"where statement" +where +"data set option" site:sas.com
Message was edited by: sbb