Re: performance of insert/delete/update

On Mon, 2002-11-25 at 21:30, Tom Lane wrote:
> Ron Johnson  writes:
> > On Mon, 2002-11-25 at 18:23, scott.marlowe wrote:
> >> The next factor that makes for fast inserts of large amounts of data in a 
> >> transaction is MVCC.  With Oracle and many other databases, transactions 
> >> are written into a seperate log file, and when you commit, they are 
> >> inserted into the database as one big group.  This means you write your 
> >> data twice, once into the transaction log, and once into the database.
> 
> > You are just deferring the pain.  Whereas others must flush from log
> > to "database files", they do not have to VACUUM or VACUUM ANALYZE.
> 
> Sure, it's just shuffling the housekeeping work from one place to
> another.  The thing that I like about Postgres' approach is that we
> put the housekeeping in a background task (VACUUM) rather than in the
> critical path of foreground transaction commit.

If you have a quiescent point somewhere in the middle of the night...

It's all about differing philosophies, though, and there's no way
that Oracle will re-write Rdb/VMS (they bought it from DEC in 1997
for it's high-volume OLTP technolgies) and you all won't re-write
Postgres...

-- 
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| Ron Johnson, Jr.     mailto:ron.l.johnson@cox.net          |
| Jefferson, LA  USA   http://members.cox.net/ron.l.johnson  |
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| "they love our milk and honey, but preach about another    |
|  way of living"                                            |
|    Merle Haggard, "The Fighting Side Of Me"                |
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