Merge/Combine 2 columns into 1 to replace blank cells

[jos283]

As part of a large data set, 2 of my columns contain dates that basically represent the same thing, and they both have missing data in different rows.

For example:

Column A      Column B     Date_Start   Date_Begin    Column E

                                              1/1/15          1/1/15

                                              1/4/15

                                                                  1/6/15

                                              1/7/15

                                              1/9/15          1/9/15

How do I combine the Date_Start and Date_Begin columns to replace the blank cells so that I get something like this:

Date_Combine

       1/1/15

       1/4/15

       1/6/15

       1/7/15

       1/9/15

I've also tried Proc Sql, Proc Format, and simply copying Date_Begin across to Data_Start (seen at the end) but it doesn't seem to be working i.e. If Missing(Date_Start) then Date_Start = Date_Begin

Any help with the coding would be appreciated!

[kiranv_ · Accepted solution]

coalesce function will do it.

proc sql;

select coalesce(Date_Start ,  Date_Begin) as Date_Combine

from yourtable;

quit;