For example...
/*Eg. 3 records starting with J for char variable a1*/
data example;
length a1 a2 a3 a4 $ 10;input a1 a2 a3 a4;
cards;
Johnson Ketan Mike Kites
John Sawyer Sharon Michael
Joe Kitten Sue Lula
Sharon Michael SAS Doug
Pamela Tiger Woods Peyton
;
run;
In a Data step...
/* We can use the : to identify obs for which a1 starts with J */
data finder1;
set example;if a1=:'J'; /*keep obs whose a1 values start with J*/
run;
In a Proc step...
var a:; /*display variables that start with 'a' i.e. a1,a2,a3,a4*/
where a1=:'J';/*keep obs whose a1 values start with J*/
However in SQL, the datastep colon modifiers (i.e. =: 'Alphabet', >: 'Alphabet' and <: 'Alphabet') do not work....But fortunately SAS provided string comparison operators as below to achieve similar tasks...
Truncated string comparison operators are used to compare two strings. They differ from conventional comparison operators in that, before executing the comparison, PROC SQL truncates the longer string to be the same length as the shorter string. The truncation is performed internally; neither operand is permanently changed. The following table lists the truncated comparison operators:
Truncated String Comparison Operators
| ||
Symbol
|
Definition
|
Example
|
EQT
|
equal to truncated strings
|
where Name eqt 'Aust';
|
GTT
|
greater than truncated strings
|
where Name gtt 'Bah';
|
LTT
|
less than truncated strings
|
where Name ltt 'An';
|
GET
|
greater than or equal to truncated strings
|
where Country get 'United A';
|
LET
|
less than or equal to truncated strings
|
where Lastname let 'Smith';
|
NET
|
not equal to truncated strings
|
where Style net 'TWO';
|
/* The same as above but with eqt comparison operators */
proc sql;
create table finder2 asselect * from example
where a1 eqt 'J'; /*keep obs whose a1 values start with J*/
quit;
Reference
http://support.sas.com/onlinedoc/913/getDoc/en/sqlproc.hlp/a001334118.htm
