To Escape % Character in SAS PROC SQL

Suppose you want to run a query to find all records containing the pattern "REQUIRED" in a certain column, the SQL where clause will look something as follows:

where thetextfield like "%REQUIRED%"

But if you use it inside SAS, SAS will interpret the %REQUIRED as a macro and throw an error.  Here is how you can escape the % character:

%let pattern=%nrstr(%%)REQUIRED%str(%%);
proc sql;
create table new_dataset as
select * from dataset
where thetextfield like "&pattern.";
quit;

You can also put the code inside a macro, and have the pattern "REQUIRED", etc as a parameter to be passed into the macro.

%macro get_records_with_pattern(pattern);
    %let patternlike=%nrstr(%%)&pattern.%str(%%);
    proc sql;
    create table new_dataset as
    select * from dataset
    where thetextfield like "&patternlike.";
    quit;
%mend get_records_with_pattern;

Now you can call the macro with the parameter REQUIRED and many more.

%get_records_with_pattern(REQUIRED);
%get_records_with_pattern(ACCEPTED);
%get_records_with_pattern(PASSED);