Re: [PERFORM] Bypassing useless ORDER BY in a VIEW

2008-02-28 Thread Dean Gibson (DB Administrator)
On 2008-02-28 09:13, Tom Lane wrote: A rule of thumb is that ORDER BY in a view is bad design, IMHO. regards, tom lane I was surprised to find out that apparently it's also a PostgreSQL extension; standard SQL apparently disallows ORDER BY in VIEWs:

Re: [PERFORM] Q on views and performance

2008-02-23 Thread Dean Gibson (DB Administrator)
On 2008-02-23 05:59, Kynn Jones wrote: On Fri, Feb 22, 2008 at 8:48 PM, Dean Gibson (DB Administrator) [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote: ... Since you have experience working with views, let me ask you this. The converse strategy to the one I described originally would

Re: [PERFORM] Q on views and performance

2008-02-23 Thread Dean Gibson (DB Administrator)
On 2008-02-23 07:08, Dean Gibson (DB Administrator) wrote: ... SELECT word1, word1 FROM S JOIN txt ON word = word1 WHERE type1 = int1 AND type2 = int2; ... Oops that should be: SELECT word1, word2 FROM S JOIN txt ON word = word1 WHERE type1 = int1 AND type2 = int2; -- Mail to my

Re: [PERFORM] Q on views and performance

2008-02-23 Thread Dean Gibson (DB Administrator)
On 2008-02-23 08:21, Kynn Jones wrote: ... 3. Why not write: CREATE VIEW txt AS SELECT a1.word AS word1, a1.type AS type1, a2.word AS word2, a2.type AS type2 FROM T a1 [LEFT] JOIN T a2 USING( zipk ); -- Use LEFT if appropriate SELECT word1, word1 FROM S

Re: [PERFORM] Q on views and performance

2008-02-23 Thread Dean Gibson (DB Administrator)
On 2008-02-23 08:49, Dean Gibson (DB Administrator) wrote: Why 10,000 views??? What's wrong with the ONE view above? You DON'T want to be defining VIEWs based on actual tables VALUES; leave that to the SELECT. For that matter, what's wrong with the final SELECT I listed (below)? SELECT

Re: [PERFORM] Q on views and performance

2008-02-22 Thread Dean Gibson (DB Administrator)
On 2008-02-22 12:49, Kynn Jones wrote: Of course, I expect that using views Vint1 and Vint2... would result in a loss in performance relative to a version that used bona fide tables Tint1 and Tint2. My question is, how can I minimize this performance loss? That used to be my thoughts too,

Re: [PERFORM] Optimizing No matching record Queries

2008-02-12 Thread Dean Gibson (DB Administrator)
On 2008-02-12 13:35, Pallav Kalva wrote: Hi, ... Table Definitions \d listing.listingstatus Table listing.listingstatus Column |Type | Modifiers

Re: [PERFORM] Upgraded from 7.4 to 8.1.4 QUERIES NOW SLOW!!!

2007-09-21 Thread db
Old servers that housed 7.4 performed better than 8.1.4 version...are there any MAJOR performance hits with this version??? I set the postgresql.conf setting to equal that of 7.4 and queries still run SLOW on 8.1.4... We need to find a specific query that is slow now that was fast before,

Re: [PERFORM] Long Running Commits - Not Checkpoints

2007-09-14 Thread db
I'm having a problem with long running commits appearing in my database logs. It may be hardware related, as the problem appeared when we moved the database to a new server connected to a different disk array. The disk array is a lower class array, but still more than powerful enough to

Re: [PERFORM] [Again] Postgres performance problem

2007-09-11 Thread db
Last time I had this problem i solved it stopping website, restarting database, vacuumm it, run again website. But I guess this is going to happen again. I would like to detect and solve the problem. Any ideas to detect it? Do you have very long transactions? Maybe some client that is