Hi naja, test those two versions (or three now) and report back to the group. :) even if some smarty-pants thinks he knows the answer its always good to confirm things are as they should be.
On Wed, Jun 12, 2013 at 11:54 PM, Sanjay Subramanian < sanjay.subraman...@wizecommerce.com> wrote: > Hi > > I would actually do it like this…so that the set on the left of JOIN > becomes smaller > > SELECT a.item_id, a.create_dt > FROM > ( SELECT > item_id, create_dt > FROM > A > WHERE > item_id = 'I001' > AND > category_name = 'C001' > ) a > JOIN > b > ON > a.item_id = b.item_id > ; > > > From: Naga Vijay <nvti...@gmail.com> > Reply-To: "user@hive.apache.org" <user@hive.apache.org> > Date: Wednesday, June 12, 2013 9:17 PM > To: "user@hive.apache.org" <user@hive.apache.org> > Subject: Enhancing Query Join to speed up Query > > Hi, > > Which of the two query options is better? > > SELECT a.item_id, a.create_dt > FROM a JOIN b > ON (a.item_id = b.item_id) > WHERE a.item_id = 'I001' > AND a.category_name = 'C001'; > > - or - > > SELECT a.item_id, a.create_dt > FROM a JOIN b > ON (a.item_id = b.item_id AND a.item_id = 'I001') > WHERE a.category_name = 'C001'; > > Thanks > Naga > > CONFIDENTIALITY NOTICE > ====================== > This email message and any attachments are for the exclusive use of the > intended recipient(s) and may contain confidential and privileged > information. Any unauthorized review, use, disclosure or distribution is > prohibited. If you are not the intended recipient, please contact the > sender by reply email and destroy all copies of the original message along > with any attachments, from your computer system. If you are the intended > recipient, please be advised that the content of this message is subject to > access, review and disclosure by the sender's Email System Administrator. >
