Hello,   I want to write a script to sum all ascii values by the column on SAS dataset and a script sample like follows. Actually, the script can be run normally with generate result successfully. But I face a problem that the performance is very slow if the number of selections are over milliion. Could some one help me to settle the performance issue? Many thanks!   %macro sqlloop; %LET numrecords  = 0;  PROC SQL  noprint; select count(*) into :numrecords from test.convertsac where  flag='Y' and tab_name like 'TB_%%'; quit; %if &numrecords>0 %then %do;  PROC SQL  noprint outobs=&numrecords; select tab_name, col_name into :tab1 - :tab%left(&numrecords), :col1 - :col%left(&numrecords) from  test.convertsac where flag='Y' and tab_name like 'TB_%'; %DO x=1 %TO &numrecords; %let tbname  = &&tab&x ; %let colname  = &&col&x ; select count(*) into :numobs from test.&tbname where &colname is not null; quit;  %PUT &tbname &colname   =======START========;   %LET totalasc  = 0;   %if &numobs>0 %then %do;     PROC SQL  noprint outobs=&numobs;     select &colname     into :tmp1 - :tmp%left(&numobs)      from test.&tbname  where &colname is not null;         %DO k=1 %TO &numobs;       %LET STRING= %sysfunc(TRIM(&&tmp&k));       %LET ascsum = 0;       %do i = 1 %to %length(&STRING);             %let ischara=%substr(&STRING,&i,1);          %let ischara=%str(&ischara);                       %let asc =%sysfunc(rank(%bquote(&ischara)));           %if &asc=0 %then %do;            %let asc =32;            %end;            %let ascsum=%eval(&ascsum + &asc) ;         %end;       %LET totalasc=%eval(&totalasc + &ascsum) ;      %END;      %PUT &tbname &colname &totalasc  =======END======== PROGRESS= &x  / &numrecords;    %end;      %else  %do;         %PUT &tbname &colname &totalasc   =======END======== PROGRESS= &x  / &numrecords;    %end; PROC SQL noprint; update test.convertsac set ascii=&totalasc, flag='N' where tab_name ="&&tbname" and col_name="&&colname"; %END; %END;  QUIT;  %mend;  %sqlloop; ... View more