3 Table Join with group by and order by clauses

Question

I am porting from MySQL to Oracle 8i. I have a three Table Join in MySQL as follows:
select distinct TO_DAYS(l.listend)-TO_DAYS(NOW()) AS daysLeft, i.minbid, l.listend, i.itemid, i.itemtitle, l.listingid, l.lendstart, l.lendend, l.status, MAX(b.amount) AS curBid, COUNT(b.amount) AS numBids from TBL_ITEMS i, TBL_LISTING l LEFT JOIN TBL_BIDS b ON l.listingid=b.listingid where i.itemid = l.itemid AND l.status='1' AND (TO_DAYS(l.listend)-TO_DAYS(NOW()) >= 0) AND i.catcode LIKE'12__' GROUP BY listingid order by curBid DESC, daysLeft;
It performs an straight join on the first 2 tables (TBL_ITEMS and TBL_LISTING) and a LEFT JOIN between the previous result set and TBL_BIDS. TBL_BIDS uses a group by clause to obtain MAX and COUNT info. This final result set is the sorted (ORDER BY).
I have tried to reconstruct this type of call in Oracle and have failed. Several problems that I have notices: Oracle does not let me pull in additional columns when doing a GROUP BY clause.
(see below for my work around)
I have worked around the problem by creating a TABLE with the group by functionality and doing a straing 3 table join. (NOTE: I cannot create a view because use a LIKE function in the call... view dont have indexes). However, when I try to alias the column that returns DATE subtraction ("l.listend-TRUNC(SYSDATE) daysLeft" OR "l.listend-TRUNC(SYSDATE) dayLeft") I cannot use the LIKE statement.
Here is my question. How do I port the above 3-table MySQL call to Oracle. Why am I having these problems (is it the Oracle optimizer?) and how do I avaopid them in the future.
I really appreciate anyone's input. Thanks,
Inder
WORK AROUND:
FIRST STEP:
"create TABLE BIDSUM as
select l.listingid, COUNT(b.amount) numBids, MAX(b.amount) curBid from TBL_LISTING l, TBL_BIDS b where l.listingid=b.listingid(+) group by (l.listingid);"
NEXT STEP:
select i.minbid, i.itemtitle, l.lendstart-TRUNC(SYSDATE), l.lendend, l.listingid, l.status, s.numbids, s.curbid from TBL_ITEMS i, TBL_LISTING l, BIDSUM s where l.listingid=s.listingid AND i.itemid=l.itemid AND l.status='1' AND i.catcode LIKE '12%';
THIS ALSO WORKS (no LIKE):
"select i.minbid, i.itemtitle, l.lendstart-TRUNC(SYSDATE) daysLeft, l.lendend, l.listingid, l.status, s.numbids, s.curbid from TBL_ITEMS i, TBL_LISTING l, BIDSUM s where l.listingid=s.listingid AND i.itemid=l.itemid AND l.status='1' AND i.catcode='12'";
BUT THIS DOES NOT (alias the DATE arimetic)
select i.minbid, i.itemtitle, l.lendstart-TRUNC(SYSDATE) daysLeft, l.lendend, l.listingid, l.status, s.numbids, s.curbid from TBL_ITEMS i, TBL_LISTING l, BIDSUM s where l.listingid=s.listingid AND i.itemid=l.itemid AND l.status='1' AND i.catcode LIKE '12__';

Answer 1

I am porting from MySQL to Oracle 8i. I have a three Table Join in MySQL as follows:
select distinct TO_DAYS(l.listend)-TO_DAYS(NOW()) AS daysLeft, i.minbid, l.listend, i.itemid, i.itemtitle, l.listingid, l.lendstart, l.lendend, l.status, MAX(b.amount) AS curBid, COUNT(b.amount) AS numBids from TBL_ITEMS i, TBL_LISTING l LEFT JOIN TBL_BIDS b ON l.listingid=b.listingid where i.itemid = l.itemid AND l.status='1' AND (TO_DAYS(l.listend)-TO_DAYS(NOW()) >= 0) AND i.catcode LIKE'12__' GROUP BY listingid order by curBid DESC, daysLeft;
It performs an straight join on the first 2 tables (TBL_ITEMS and TBL_LISTING) and a LEFT JOIN between the previous result set and TBL_BIDS. TBL_BIDS uses a group by clause to obtain MAX and COUNT info. This final result set is the sorted (ORDER BY).
I have tried to reconstruct this type of call in Oracle and have failed. Several problems that I have notices: Oracle does not let me pull in additional columns when doing a GROUP BY clause.
(see below for my work around)
I have worked around the problem by creating a TABLE with the group by functionality and doing a straing 3 table join. (NOTE: I cannot create a view because use a LIKE function in the call... view dont have indexes). However, when I try to alias the column that returns DATE subtraction ("l.listend-TRUNC(SYSDATE) daysLeft" OR "l.listend-TRUNC(SYSDATE) dayLeft") I cannot use the LIKE statement.
Here is my question. How do I port the above 3-table MySQL call to Oracle. Why am I having these problems (is it the Oracle optimizer?) and how do I avaopid them in the future.
I really appreciate anyone's input. Thanks,
Inder
WORK AROUND:
FIRST STEP:
"create TABLE BIDSUM as
select l.listingid, COUNT(b.amount) numBids, MAX(b.amount) curBid from TBL_LISTING l, TBL_BIDS b where l.listingid=b.listingid(+) group by (l.listingid);"
NEXT STEP:
select i.minbid, i.itemtitle, l.lendstart-TRUNC(SYSDATE), l.lendend, l.listingid, l.status, s.numbids, s.curbid from TBL_ITEMS i, TBL_LISTING l, BIDSUM s where l.listingid=s.listingid AND i.itemid=l.itemid AND l.status='1' AND i.catcode LIKE '12%';
THIS ALSO WORKS (no LIKE):
"select i.minbid, i.itemtitle, l.lendstart-TRUNC(SYSDATE) daysLeft, l.lendend, l.listingid, l.status, s.numbids, s.curbid from TBL_ITEMS i, TBL_LISTING l, BIDSUM s where l.listingid=s.listingid AND i.itemid=l.itemid AND l.status='1' AND i.catcode='12'";
BUT THIS DOES NOT (alias the DATE arimetic)
select i.minbid, i.itemtitle, l.lendstart-TRUNC(SYSDATE) daysLeft, l.lendend, l.listingid, l.status, s.numbids, s.curbid from TBL_ITEMS i, TBL_LISTING l, BIDSUM s where l.listingid=s.listingid AND i.itemid=l.itemid AND l.status='1' AND i.catcode LIKE '12__';