Sql (lpad function)

Question

I came across this function in a certification book i.e. lpad(' ',<integer>) in a hierarchial query like this:
SELECT LEVEL, EMPNO, LPAD(' ',LEVEL * 2) || JOB TITLE FROM EMP
START WITH EMPNO = 7839
CONNECT BY MGR = PRIOR EMPNO;
The query works fine. But the actual syntax for lpad fn is lpad(<string>,<number of times to pad>[,padding string]). So why is there a difference in syntax for lpad?

Answer 1

Hi,
ramvidya wrote:
I came across this function in a certification book i.e. lpad(' ',<integer>) in a hierarchial query like this:
SELECT LEVEL, EMPNO, LPAD(' ',LEVEL * 2) || JOB TITLE FROM EMP
START WITH EMPNO = 7839
CONNECT BY MGR = PRIOR EMPNO;
The query works fine. But the actual syntax for lpad fn is lpad(<string>,<number of times to pad>[,padding string]). So why is there a difference in syntax for lpad?Sorry, I don't understand the question.
You seem to be saying the syntax for LPAD is different from something else, but what is that something else?
Are you saying that the actual way it is used:
LPAD(' ',LEVEL * 2)differs from the documentation:
lpad(<string>,<number of times to pad>[,padding string])? They look the same to me.
The documentation says the first argument is a string: the example uses the string ' ' (a single space).
The documentation says the second argument is a number: the example uses LEVEL * 2. (The pseudo-column LEVEL is a number, and the product of two numbers, like LEVEL and 2, is also a number.)
The documentation says the third argument (padding string) is optional (the square brackets mean that it can be skipped): the example skips the third argument.
Edited by: Frank Kulash on May 10, 2010 11:58 PM