Mladen, don't want to start Postgres-related discussion on Oracle's list,
but...
Coming to Postgres with Oracle background, I agree with you on hints.
Your other points seem to be sketchy/perfunctory.
Storing undo information in the table itself is just Postgres way to
implement MVCC (one of what you call "big three" dbs, SQL Server got MVCC
implemented only starting with SQL Server 2008). As for performance during
table scans, Oracle has to visit UNDO segment, so...
Parallelism: latest version of PG has some implementation of the feature,
and it'll get more development in future versions.
Partitioning: not as rich as in Oracle (you're right, there is no global
indexes), but it serves the purpose of the applications I'm using it with.
There are many contributors: individuals and companies, other than
EnterpriseDB, besides community version is being used much wider than
EnterpriseDB.
All-in-all, PG has its place and usage, not "every nail needs a huge
hammer" like Oracle.
Igor N.
On Thu, Aug 18, 2016 at 10:50 PM, Mladen Gogala <gogala.mladen@xxxxxxxxx>
wrote:
On 08/18/2016 04:28 PM, kyle Hailey wrote:
Thanks Michael.
Any recommendations for Postgres performance specifically?
This is probably the best book on the market:
https://www.amazon.com/PostgreSQL-High-Performance-Gregory-Smith-ebook/dp/
B0057G9RUG
You will probably also be interested in this:
http://pghintplan.osdn.jp/pg_hint_plan.html
https://dbwhisperer.wordpress.com/2015/03/21/postgresql-
hints-and-dbms_stats/
Postgres community has a famously negative attitude toward hints:
https://wiki.postgresql.org/wiki/OptimizerHintsDiscussion
You can even find comic texts like this:
http://it.toolbox.com/blogs/database-soup/why-postgresql-
doesnt-have-query-hints-44121
BTW, I am the Oracle DBA mentioned in that text. I have a knack for
bringing out the best in people. I helped our good baker turned DB
architect to reach the apex of stupidity. Needless to say, the hints are
now available, but the official Postgres community doesn't want to talk
about them and still considers them as something not worthy of being
mentioned in polite society.
Postgres architecture is bad, it prevents it from performing well. The
problem is the fact that undo information is stored within the table
itself. What that means for a full table scan is not hard to imagine. There
is no parallelism of any kind and partitioning is a joke. It is not
possible to create a global index. The open source version of Postgres is,
in my humble opinion, just an engine for selling EnterpriseDB, which does
have hints. Problem with open source databases is in the old adage, which
is still valid: you get what you pay for. They're simply not capable of
replacing any of the big 3 commercial databases.
I just started at Amazon RDS and one of my first tasks will be working on
performance monitoring for Postgres.
- Kyle
http://kylehailey.com
Oh you poor thing! I wish you the best of luck!
On Tue, Aug 2, 2016 at 7:07 PM, Vijay Sehgal <vijaysehgal21@xxxxxxxxx>
wrote:
Thanks for your help, Michael and Matthew.
Regards,
Vijay Sehgal
On Aug 1, 2016, at 7:34 PM, Michael Cunningham <napacunningham@xxxxxxxxx>
wrote:
Here are some of what I have been using.
PostgreSQL Video Tutorials (30 videos)
This video series uses EnterpriseDB and does some things for you
automatically.
https://www.youtube.com/watch?v=CkjQSkWl0F0&list=PLFRIKEguV5
4bgwAcgFiOs5GMo3q2DhVDj
PostgreSQL Installation
I like this video because it does not use EnterpriseDB and you get to
learn a little more about the install.
https://www.youtube.com/watch?v=y2haO82SPd4
PostgreSQL Docs
These docs are really well written in my opinion
https://www.postgresql.org/docs/9.5/static/index.html
Michael
On Mon, Aug 1, 2016 at 1:12 PM, vijayrsehgal <vijaysehgal21@xxxxxxxxx>
wrote:
Dear Experts,
Our Team has to build skills on PostgreSql, we have to help developers
and also take tasks of DBA. The team has worked mostly only on Oracle.
I would appreciate if you could please point me to some books and also
trainings available either online or in-person, so that our team can take
this new learning forward.
Thanking you all for your help and time.
Kind Regards,
Vijay Sehgal
--
Michael Cunningham
--
Mladen Gogala
Oracle DBAhttp://mgogala.freehostia.com
