在SAS宏中执行IF ELSE逻辑

Question

我是SAS新手。尝试做简单的if-else逻辑并将其合并到循环中。有问题;无法解决。

%macro iterate ();
    %let lastCount = 0;
    %let currentCount=0;
    %let infiniteLoop= 1;

%do %while(&infiniteLoop=1); 

/* ..some sql logic */

proc sql noprint;
select count(*) into :currentCount from table1;
quit;

IF &currentCount=&lastCount 
THEN &infiniteLoop=0
ELSE  &lastCount = &currentCount;

%put 'show values: ' &lastCount;
%end;
%mend iterate;

%iterate();
run;

出现“声明无效等错误。

Answer 1

您需要使用%if %then %else代替if then else

http://support.sas.com/documentation/cdl/en/mcrolref/61885/HTML/default/viewer.htm#a000543542.htm

并使用％let覆盖宏变量。

像这样

    %IF &currentCount=&lastCount %THEN %let infiniteLoop=0 ;
    %ELSE  %let lastCount = &currentCount;