Re: performance of insert/delete/update

Ron Johnson <ron.l.johnson@cox.net> 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.

            regards, tom lane