one to many merge in SAS to complete lines - panel-data

Question

I am struggling with merge in the statistics programm SAS and hope you guys can help me:
I have Dataset that I want to join together
it looks smth. like this:
input:
id |var1 |var2 |var3 |var4 |Var5
>--------------------------------<
1 |A1 |B1 |C1 | -- | 0 |
1 |A2 |B2 |-- | D2 | 1 |
desired output:
id |var1 |var2 |var3 |var4 |Var5
>--------------------------------<
1 |A1 |B1 |C1 | D2| 0|
1 |A2 |B2 |C1 | D2| 1|
I tried to seperate the data set in two by if "Var5=0/1 then delete"
statments and then merging them together like:
Data example1
id |var1 |var2 |var3 |var4 |Var5
>----------------------------<
1 |A1 |B1 |C1 | -- | 0|
Data Example2
id |var1 |var2 |var3 |var4 |Var5
>--------------------------------<
1| A2 | B2 |-- | D2| 1|
Merge code:
data Example12;
merge example1 (IN=X) example2;
by persnr;
IF x=1;
run;
but this results in something like:
id |var1 |var2 |var3 |var4 |Var5
1|A1 |B1 |C1| D2| 0|
1|A1 |B1 |C1| D2| 0|
any help greatly appreciated.

Answer 1

If it is the case that only one record per ID will have a non missing value for the VAR3 or VAR4 then you could use dataset options to set up a one-to-many merge that would get the value of VAR3 and VAR4 merged onto all rows for that ID.
First let's setup your example data:
data have ;
input (id var1-var4) ($) var5 ;
cards;
1 A1 B1 C1 . 0
1 A2 B2 . D2 1
;
Now try the merge:
data want ;
merge have(drop=var3 var4)
have(keep=id var3 where=(not missing(var3)))
have(keep=id var4 where=(not missing(var4)))
;
by id;
run;