Set by option

[aaaaa34]

Hi,

What does by option do in:
data aaa;
set bbb;
by var1 var2;
run;

[PaigeMiller · Accepted solution]

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@aaaaa34 wrote:

What does by option do in:
data aaa;
set bbb;
by var1 var2;
run;

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In this case, the BY statement with a single dataset listed in the SET statement does almost nothing. It does allow FIRST.  and LAST. variables to be created and used, but your code doesn't use them, so essentially BY does nothing in your code.

[Kurt_Bremser]

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@aaaaa34 wrote:
Hi,

What does by option do in:
data aaa;
set bbb;
by var1 var2;
run;

---

It forces a sort condition by var1 var2. If a deviation from the sort order is encountered during execution, the step will terminate with an ERROR.

Other than that, the by statement in your code has no effect, as neither first. or last. is used.