How to merge two datasets with the same column names into one dataset

[Jarvin99]

Hello, below is an example of my two datasets:

dataset A:

id	env	water	transport	production
1	0	0	0	0
2	1	0	1	0
3	0	0	0	1
4	0	0	1	0

dataset B:

id	env	water	transport	production
1	1	0	0	0
2	0	0	0	0
3	0	0	0	0
4	1	0	1	1

Just a background, why two datasets have the same column names is because I split my original data into two subsamples and let them run through the same codes to achieve this.

I want that as long as there is '1' in one of the datasets, the combined table should reflect '1'.

Below is my desired outcome:

id	env	water	transport	production
1	1	0	0	0
2	1	0	1	0
3	0	0	0	1
4	1	0	1	1

I know there are probably time-consuming ways to achieve the desired outcome by renaming one of the table's column names, merging by id, summing the columns, restricting to greater than 1, and so on. However, I want to know if there is a fast and non-tedious way for operation as the reason why I initially split is that the original dataset was too huge. Hopefully, the expert can provide a more efficient method. Thank you. 

[Kurt_Bremser · Accepted solution]

Stack the two datasets, then use PROC MEANS:

data stacked,
set a b;
by id;
run;

proc means data=stacked;
by id;
var env water transport production;
output
  out=want (drop=_type _freq_)
  max()=
;
run;

[andreas_lds]

A merge could be used, but requires renaming the variables of one dataset:

data want;
   merge have_a have_b(rename=(env= b_env water=b_water transport = b_transport production = b_production));   
   by id;
   
   env = env or b_env;
   water = water or b_water;
   transport = transport or b_transport;
   production = production or b_production;
   
   drop b_:;
run;