| From: | Pavel Stehule <stehule(at)kix(dot)fsv(dot)cvut(dot)cz> |
|---|---|
| To: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | bitmapscan test, no success, bs is not faster |
| Date: | 2005-04-26 11:20:38 |
| Message-ID: | Pine.LNX.4.44.0504261250060.1977-300000@kix.fsv.cvut.cz |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Hello,
I tested bitmap scan and maybe I didnt find good examples, but with bitmap
scan is slower than hashjoin. Only when I use non otiptimized SELECT bps
was little bit faster. All my SELECTs are equal.
bsp off bsp on (ms)
SELECT 1 39.798 37.993
SELECT 2 0.310 0.330
SELECT 3 0.387 0.416
SQL and query plans are in attachment.
Regards
Pavel Stehule
| Attachment | Content-Type | Size |
|---|---|---|
| output.txt | text/plain | 7.9 KB |
| aaa.sql | text/plain | 1.0 KB |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Greg Sabino Mullane | 2005-04-26 11:43:31 | Re: [HACKERS] Continue transactions after errors in psql |
| Previous Message | apoc9009@yahoo.de | 2005-04-26 09:43:21 | Re: Tablepartitioning: Will it be supported in Future? |