Return a collection

Question

I am having trouble coming up with a plan for search functionality for my UI. I have an application that talks to a middle teir in .NET, the middle tier accesses the Oracle database.
People are going to want to search by multiple fields that come from multiple tables. It was suggested on the .NET forums that I write a procedure that takes all possible search fields and then just check if they are null or not and come up with a dynamic query. Seems like a possible solution, but maybe not the best.
So, I am toying around with that idea, but cannot figure out how I can return a varibale length collection of IDs (number) from a function or procedure. Or at least what the best way to do that is.
My colleague came up with some code, but I don't understand it and neither does he, it was put together from some googled examples trial and error.
But rather than try to decypher what we came up with I thought I'd ask what the preferred method of doing this is and if someone is kind enough to write up an example?
From what I can tell, there are problems getting a varray back on the .NET side, but haven't played with it too much yet.

Answer 1

Ok, I didn't understand what it was doing fully. Now I do. Works nicely. I am having trouble with the bulk collect part though. I get an error when I change my current loop to
OPEN cursorPersonIDs FOR finalQuery USING firstName, lastName, phoneNumber, emailAddress;
FETCH cursorPersonIDs BULK COLLECT INTO results;
Error: "inconsistent datatypes: expected UDT got NUMBER"
Here is my current code: (Sorry the forum irradicated my formatting)
CREATE OR REPLACE FUNCTION NEWDB."F_FIND_PERSON"(firstName IN varchar2,
lastName IN varchar2,
phoneNumber IN varchar2,
emailAddress IN varchar2)
RETURN TBL_IDS
IS
TYPE RefCursor IS REF CURSOR;
selectPart varchar2(32) := 'SELECT PPL.PERSON_ID ';
fromPart varchar2(128) := 'FROM PEOPLE PPL ';
wherePart varchar2(1024) := 'WHERE 1=1 ';
finalQuery varchar2(1024);
cursorPersonIDs RefCursor;
result number;
results TBL_IDS := TBL_IDS();
counter integer := 0;
BEGIN
-- PEOPLE table already included
-- First Name
IF firstName IS NOT NULL THEN
wherePart := wherePart || 'AND (PPL.NAME_FIRST = :pFirstName OR PPL.NAME_FIRST IS NULL) ';
ELSE
wherePart := wherePart || 'AND :pFirstName IS NULL ';
END IF;
-- Last Name
IF lastName IS NOT NULL THEN
wherePart := wherePart || 'AND (PPL.NAME_LAST = :pLastName OR PPL.NAME_LAST IS NULL) ';
ELSE
wherePart := wherePart || 'AND :pLastName IS NULL ';
END IF;
-- PHONE_NUMBERS table requires join
IF phoneNumber IS NOT NULL THEN
fromPart := fromPart || ', PHONE_NUMBERS PHN ';
wherePart := wherePart || 'AND PPL.PERSON_ID = PHN.CONTACT_ID ';
-- Phone Number
IF phoneNumber IS NOT NULL THEN
wherePart := wherePart || 'AND (PHN.PHONE_NUMBER = :pPhoneNumber OR PHN.PHONE_NUMBER IS NULL) ';
ELSE
wherePart := wherePart || 'AND :pPhoneNumber IS NULL ';
END IF;
ELSE
wherePart := wherePart || 'AND :pPhoneNumber IS NULL';
END IF;
-- EMAIL_ADDRESSES table requires join
IF emailAddress IS NOT NULL THEN
fromPart := fromPart || ', EMAIL_ADDRESSES EML ';
wherePart := wherePart || 'AND PPL.PERSON_ID = EML.CONTACT_ID ';
-- Email Address
IF emailAddress IS NOT NULL THEN
wherePart := wherePart || 'AND (EML.ADDRESS = :pEmailAddress OR EML.ADDRESS IS NULL) ';
ELSE
wherePart := wherePart || 'AND :pEmailAddress IS NULL ';
END IF;
ELSE
wherePart := wherePart || 'AND :pEmailAddress IS NULL ';
END IF;
-- Execute the query
finalQuery := selectPart || fromPart || wherePart;
OPEN cursorPersonIDs FOR finalQuery USING firstName, lastName, phoneNumber, emailAddress;
LOOP
FETCH cursorPersonIDs INTO result;
EXIT WHEN cursorPersonIDs %NOTFOUND;
results.extend;
counter := counter + 1;
results(counter) := TYPE_ID(result);
END LOOP;
CLOSE cursorPersonIDs;
RETURN results;
END;
Edited by: brekehan on Mar 19, 2010 7:46 AM