I am trying to merge table 1 with table 2; however, table 1 has a visit # field and lab date fields, while table 2 only has an event date field. I want the merged table to show all labs that have a specific value at a certain visit and also include any corresponding events that happen on that same day or close to that date. The problem is an event date might be different than a lab date. Currently my table looks like this:
I agree with KSharp, the narrative and the examples are confusing. Particularly as the narrative seems to be missing variables and you have 3 heading and 4 pieces of data in the sample.
Reading between the lines, I generally attack this sort of problem with PROC SQL. The idea of a "fuzzy" match or "nearest" match on dates is a natural for the BETWEEN operator on a JOIN. There are good examples of this in the SQL reference manual as well as in several BBUs.