UPDATE statement - Fill null values with previous non-null values within same group

[renanm]

I've been looking for a way to fill null values with previous non-null values within the same group. 

While I know how to do that in SQL it took me a while to figure out in SAS. 

I have been able to figure out the code that will accomplish this. However, I'd like this to apply to only about 10 variables of about 100 variables I have in my data set. 

is there a way to apply the update to only selected variables with the below code? 

data Want;
   update MyData(obs=0) MyData;
   by ID;
   output;
run;
 
proc print data=Want;
run;

Thanks in advance !

[Tom]

Just re-read those variables from the dataset.

Let's day you want to update only VAR1-VAR5 .

data Want;
   update MyData(obs=0) MyData ;
   by ID;
   set MyData (drop=Var1-Var5);
   output;
run;

[renanm]

Hi @Tom , thanks for the reply. 

In your suggestion below, wouldn't the output data only contain VAR1-VAR5?

Ultimately I need the output dataset to contain all 100 variables VAR1-VAR100 but only retro-fill VAR1-VAR5. 

Thanks !

[Tom]

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@renanm wrote:

Hi @Tom , thanks for the reply. 

In your suggestion below, wouldn't the output data only contain VAR1-VAR5?

Ultimately I need the output dataset to contain all 100 variables VAR1-VAR100 but only retro-fill VAR1-VAR5. 

Thanks !

---

No. Try it.