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WARNING: You may have unbalanced quotation marks.

SAS can allow the strings up to 32,767 characters long but some times SAS will write a Warning message WARNING: The quoted string currently being processed has become more than 262 characters long. You may have unbalanced quotation marks., when you try to keep a character string longer than 262 characters to a variable.  It is hard to look back at the SAS code to search for unbalanced quotes.
To make it more clearly I am going to show an example.

I want to add a 263 characters long name to a variable (longvar) and to do that I will simply use a data step… and when I do that I will see the WARNING message in Log.

data TEST;
x="(SEE DOCTOR'S LETTER)3RD ADMINISTRATION OF MTX WAS DELAYED BY 14 DAYS AND WAS REDUCED TO 1G/M2 INSTEAD OF 5G/M2, PROBLEMS, E.COLI SEPSIS WITH HEART INSUFFICIENCY WITH SINUS TACHYCARDY, PARALYTIC ILEUS, TACHYPNEA , PATIENT DIED ON 21.04.98 FROM MULTIORGAN FAILURE.";
y=length(x);
put x;
run;

LOG FILE:

There is a SAS option (NOQUOTELENMAX) which will take care of the WARNING message.

Options noQuoteLenMax; *Just before the Data step;

Don’t forget to change back to Options QuoteLenMax; after the end of the Data step.

Options noQuoteLenMax;

CALL EXECUTE: Easy way to print or sort multiple files.

When printing multiple files, or sorting multiple datasets, the traditional method is to write multiple steps as below.

Proc print data=libref.ae; var _all_; run;
Proc print data=libref.conmed; var _all_; run;
Proc print data=libref.demog; var _all_; run;
Proc print data=libref.lab; var _all_; run;

Proc print data=libref.medhist; var _all_; run;
If you are like me who likes to simplify the traditional SAS code here is the tip. CALL EXECUTE comes to rescue here.

*Using Disctionary Tables and Call Execute;
proc sql;
create table dsn as select distinct memname from dictionary.tables
where libname="LIBREF" and memtype="DATA";
quit;

*Sorts all the datasets using Call Execute;
data _null_;
set dsn;
call execute ("proc sort data=final.||'memname||';by usubjid; run;");
run;

*Prints all the datasets using Call Execute;
data _null_;
set dsn;
call execute ("proc print data=final.||'trim(memname)||';var _all_; run;");
run;

*Using Proc Contents and Call Execute;
proc contents data=libref._all_ out=contents(keep=memname);
run;

*Create a macro variable memname with list of all the datasets; 
proc sql;
select distinct memname into:memname from contents;
quit;
%put memname;

*Sorts all the datasets using Call Execute;
data _null_;
set dsn;
call execute ("proc sort data=libref.||'trim(memname)||';by usubjid; run;");
run;

*Prints all the datasets using Call Execute;
data _null_;
set dsn;
call execute ("proc print data=libref.||'trim(memname)||';var _all_; run;");
run;

*Using SASHELP Views and Call Execute to sort the dataset by usubjid;

*Sorts all the datasets using Call Execute;
data _null_;
set sashelp.vtable (where=(libname="LIBREF"));
call execute("proc sort data=libref.||'trim(memname)||';by usubjid;run;");
run;

*Prints all the datasets using Call Execute;
data _null_;
set sashelp.vtable (where=(libname="LIBREF"));
call execute("proc print data=libref.||'trim(memname)||';by _all_;run;");
run;

*If you are not printing/sorting all the datasets in the library here is code for that.The Following code only prints 4 datasets (AE, Conmed, Demog , Lab and Medhist);

data _null_;
do dsname='ae', 'conmed', 'demog', 'lab', 'medhist';
call execute("Proc print data=libref.||'trim(dsname))||'; var _all_; run;");
end;
run;

Write a Letter using SAS/ Emailing with SAS

SAS can do many things which most of us don’t have a clue. Here is one example….

Writing a letter:

filename formltr 'C:\Documents and Settings\sreddy\Desktop\formltr.rtf';

data address;
infile datalines;
input @ 1 stno
 @ 6 lane $12.
@19 aptno $7.
@27 city $9.
@37 state $2.
@40 zip ;
datalines;
2550 Augusta Blvd Apt#203 Fairfield OH 45014
;
run;

data _null_;
retain lm 5;
set address;
file formltr;* print notitles;
put _page_;
adr1 = trim(stno) ' ' trim(lane);
put @lm adr1;
adr2 = trim(aptno);
put @lm adr2;
adr3 = trim(city) ||', '|| trim(state) ||' '|| trim(zip);
put @lm adr3;
adr4 = trim('Dear')|| ' ' ||trim('SAS') || ' ' || trim('Users,');
put / @lm adr4;
put / @lm 'StudySAS Blog offers a lot of information regarding tips and tutorials on various topics ' ;
put @lm 'in SAS. It covers basics to get started to more in-depth topics like Macros and Proc SQL.';
put @lm 'It is a great site to browse to help broaden and deepen your SAS knowledge in a variety';
put @lm 'of areas.';
put / @lm 'Thanks for visiting StudySAS Blog. ';
put //// @lm 'Sarath Annapareddy';
run;
  
  • lm: represents left margin
  • / : forward slash symbol ( / ) skips a line.
  • If you want to skip ‘N’ number of lines use ‘N’ number of flashes after the PUT statement.
  • The trim function and concatenation operator (||) are important here because without these you will get extra spaces which we probably don't want see in our letter.
The Above SAS program will create a rtf in the specified location with the following information.



Emailing with SAS




How to send an email using SAS:

filename mymail email sastest@abc.com subject="Sending Email using SAS" from=abctest@gmail.com' attach="C:\Documents and Settings\sreddy\Desktop\formltr.rtf";


data _null_;
file mymail;
put 'Hello there, Please review the attached letter.';
put 'Thanks,';
put 'Sarath';
run;
quit;

Special Missing Values in SAS

Definition: Special missing value is a type of numeric missing value that enables you to represent different categories of missing data by using the letters A-Z or an underscore.
Ref: SAS 9.1.3 language reference: concepts page no: 102

The symbol usually used to represent a missing value for a numerical variable is the period or dot. Aside from the dot, there are 27 special missing values SAS can store in numerical variables. They are the dot-underscore (._), and dot-letter (.A thru .Z). Note that these special values are case insensitive. That is, .A=.a .B=.b .C=.c etc.

If you do not begin a special numeric missing value with a period, SAS identifies it as a variable name. Therefore, to use a special numeric missing value in a SAS expression or assignment statement, you must begin the value with a period, followed by the letter or underscore, as in the following example:

x=.d;

When SAS prints a special missing value, it prints only the letter. When data values contain characters in numeric fields that you want SAS to interpret as special missing values, use the MISSING statement to specify those characters.

Example:  Consider the following data step which contains a questionnaire data (three students, three questions, and three possible responses to each question 1, 2 and 3):

data test;
/* M = multiple, U = unreadable, .=Didn’t answer */
missing answer M U;
input student question answer;
datalines;
1 1 1
1 2 2
1 3 M
2 1 U
2 2 3
2 3 2
3 1 M
3 2 .
3 3 1
;
Proc print data=test; run;
The MISSING statement is needed here to keep special missing values for the numeric variable answer. In the above example, M is used to indicate multiple responses (not allowed) and U is used to indicate an unreadable response.

Order of Missing Values for Numeric Variables:

The numeric missing value (.) is sorted before the special numeric missing value .A, and both are sorted before the special missing value .Z. SAS does not distinguish between lowercase and uppercase letters when sorting special numeric missing values.

Checking for Missing Numeric Values:

Often the SAS programmer uses the following SAS code to check for a missing numeric value:

IF VALUE=. THEN PUT "*** Value is missing";

While in most instances the above code works as intended, there are occasions where it may not catch some missing values. The above statement assumes that only a dot is present, and none of the other 27 missing numeric values, are present in your data. In exhibit 1, it was shown that the dot-Z is the highest missing value. So, a better, more inclusive way to check for a missing numeric values is:

IF VALUE <=.Z THEN PUT "*** Value is missing";
Reference: http://analytics.ncsu.edu/sesug/2005/TU06_05.PDF

The latter IF statement checks for all 28 possible missing values.

For more details on Special Missing Values Please refer, Malachy J. Foley paper … MISSING VALUES: Everything You Ever Wanted to Know

The other thing you should know is... If the MISSING option is used in PROC FREQ, you'll get a breakdown for each type of missing value. For example, given (without MISSING):


*Without MISSING option:
proc freq data=test;
tables question*answer/ nopercent nocol norow;
run;

Output:

*With MISSING option:


proc freq data=test;
tables question*answer/ nopercent nocol norow missing;
run;

output;




Disclosure:

In the spirit of transparency and innovation, I want to share that some of the content on this blog is generated with the assistance of ChatGPT, an AI language model developed by OpenAI. While I use this tool to help brainstorm ideas and draft content, every post is carefully reviewed, edited, and personalized by me to ensure it aligns with my voice, values, and the needs of my readers. My goal is to provide you with accurate, valuable, and engaging content, and I believe that using AI as a creative aid helps achieve that. If you have any questions or feedback about this approach, feel free to reach out. Your trust and satisfaction are my top priorities.