How to replace a row from another table

[jjjunyi]

Hi every one.

Now I have dataset A:

Date	AZ	WM	TG
1/1/2015	20	30	50
1/2/2015	*	*	*
1/3/2015	*	*	*
1/4/2015	*	*	*
1/5/2015	*	*	*
1/6/2015	*	*	*
1/7/2015	*	*	*
1/8/2015	*	*	*

Now I have dataset B:

Date	AZ	WM	TG
1/1/2015	10	0	12

I want dataset A look like:

Date	AZ	WM	TG
1/1/2015	10	0	12
1/2/2015	*	*	*
1/3/2015	*	*	*
1/4/2015	*	*	*
1/5/2015	*	*	*
1/6/2015	*	*	*
1/7/2015	*	*	*
1/8/2015	*	*	*

Any suggestions?

[DBailey · Accepted solution]

proc sql;

update dataset_a t1

set

     az=(select az from dataset_b where date=t1.date),

     wm=(select wm from dataset_b where date=t1.date),

     tg = (select tg from dataset_b where date=t1.date)

where exists (select * from dataset_b where date=t1.date);

quit;

[jjjunyi]

thanks but looks some error

[jjjunyi]

Never mind, I forgot to delete comma.

[Tom]

Not sure why people insist on putting commas at the end of the line instead of the beginning.  They are much harder to see out there.

[Ksharp]

Since you already have a index variable DATE, why not use MERGE statement.

data want;
 merge A B;
 by date;
run;