Cursor in Function

Question

Hi
I've been looking through the forums hoping to find a sort of similar situation as mine but to no avail. I am new to working with Oracle sql and am trying to combine a cursor into a function because the function, when a parameter is passed, returns more than one row of data. I was hoping to use the cursor to build up a string into one result and then return that but am a bit unsure of the syntax of Oracle 10g and am finding all sorts of different half-answers on the net as to what I am trying to do.
The code I have below is my attempt at creating a cursor inside the function but keep getting this following error when I compile it in Oracle developer:
Error(15,7): PLS-00215: String length constraints must be in range (1 .. 32767) for the highlighted code below. As I said I do not know what I have to actually declare here as I have declared the parameter past in as VARCHAR2 without any string length constraint and it does not return an error.
If anyone highlights that my loop is not finished it is because that is exactly right - I have not finished it yet. I will explain below the function what I am trying to do.
create or replace
FUNCTION MyFunction(number_ VARCHAR2)
RETURN VARCHAR2
IS
CURSOR C1 IS
SELECT t1.column1
  FROM from table1 t1
  LEFT OUTER JOIN table2 t2 ON t2.FKID_t3 = t3.id
  INNER JOIN table4 T4 ON t3.FKID_t4 =t4.id
  INNER JOIN table5 ON t2.FKID_t5 = t5.id
  INNER JOIN table6 t6 ON t5.FKID_t6 = t6id
  WHERE t5.number = number_
  AND t4.column4 LIKE 'condition%'
AND t6.column1 = 'string';
NAME_ VARCHAR2; <<<<<<<< Error
NAME1_ VARCHAR2; <<<<<<< Error
RESULT_ t1.column1%TYPE;
DESCRIPTION_ t6.column2%TYPE;
BEGIN
FOR i IN C1 LOOP
    NAME_ := RESULT_ || ' ' || DESCRIPTION_;
    NAME1_ :=NAME_;
    END LOOP;
RETURN(NAME1_);
END;If I run the query it will return two rows like below:
Test        Result
=====   =========
Pre          Pass
Post        PassThe result could be: Pass, fail or null
I am trying to concatenate the first row then the seocnd row into one line so it would look like:
"Pre - Pass, Post - Pass"
Can anyone help with mainly setting up the curosr in the function, not sure if it is right? I think I can manage the concatenation bit ok.
Thanks for any input.
A
Edited by: user605593 on Feb 8, 2011 11:49 AM
Edited by: user605593 on Feb 8, 2011 11:50 AM

Answer 1

user605593 wrote:
Does it look as if there any other obvious faults with the code, although not causing errors, parts of the pl/sql set-up that isn't good practice?Since you asked...
1) Neither RESULT_, DESCRIPTION_, nor NAME_ are initialized before they are used. So your loop is concatenating NULL together a bunch of times. I'm guessing that's not what you want. I'm guessing that you want to concatenate together the data from multiple rows returned from your cursor. It's a bit hard since you don't explain what this is supposed to do, but I'm guessing that you want something like
create or replace
FUNCTION MyFunction(number_ VARCHAR2)
RETURN VARCHAR2
IS
CURSOR C1 IS
SELECT t1.column1, t6.column2
  FROM from table1 t1
  LEFT OUTER JOIN table2 t2 ON t2.FKID_t3 = t3.id
  INNER JOIN table4 T4 ON t3.FKID_t4 =t4.id
  INNER JOIN table5 ON t2.FKID_t5 = t5.id
  INNER JOIN table6 t6 ON t5.FKID_t6 = t6id
  WHERE t5.number = number_
  AND t4.column4 LIKE 'condition%'
AND t6.column1 = 'string';
  NAME_ VARCHAR2; <<<<<<<< Error
  NAME1_ VARCHAR2; <<<<<<< Error
BEGIN
FOR i IN C1 LOOP
    NAME_ := i.column1 || ' ' || i.column2;
    NAME1_ :=NAME1_ || NAME_;
  END LOOP;
  RETURN(NAME1_);
END;2) If you are just trying to concatenate data from multiple rows, there are more elegant string aggregation techniques.
3) I'm not a fan of your variable naming convention. An underscore suffix is likely to cause confusion because it is relatively easy to miss. And I'm hoping that your actual variable names are more descriptive and not just NAME and NAME1.
Justin