MACROS IN SEG

[yook]

  Macro _EG_CONDITIONAL_DROPDS

%_eg_conditional_dropds(WORK.QUERY_FOR_ELIGIBILITY);

what is the purpose of this macro?

why do we need to write this code at the beginning of your code?

thanks

[ChrisHemedinger · Accepted solution]

Enterprise Guide uses this macro (and others that are similar) to avoid warnings when general PROC SQL code creates a table that might already exists. This macro drops (deletes) the table ahead of the next step, which creates an updated version.



It's not a practice that most developers have in their code, but since EG generates lots of code that can be chained together in a flow, statements like these can help avoid innocuous (but distracting) warnings.

[Reeza]

It drops the data set if it exists. This is to maintain the process integrity, makes sure that the process doesn't continue with data left over from previous run. 

I don't think it has to be at the beginning of the code, but where makes sense from a programming perspective. If you clean up all at the beginning, that's not a bad thing either.

The code for the macro is here:

http://support.sas.com/kb/38/454.html