Re: Update table performance

bedrockconstruction(at)yahoo(dot)com (Mark Makarowsky) writes:
> I have a table with 4,889,820 records in it. The
> table also has 47 fields. I'm having problems with
> update performance. Just as a test, I issued the
> following update:
>
> update valley set test='this is a test'
>
> This took 905641 ms. Isn't that kind of slow? There
> aren't any indexes, triggers, constraints or anything
> on this table. The version of Postgres is "PostgreSQL
> 8.2.4 on i686-pc-mingw32, compiled by GCC gcc.exe
> (GCC) 3.4.2 (mingw-special)". The operating
> environment is Windows 2003 Standard Edition w/service
> pack 2. It is 2.20 Ghz with 1.0 GB of RAM. Here is
> the results from Explain:
>
> "Seq Scan on valley (cost=0.00..1034083.57
> rows=4897257 width=601)"
>
> Here are the settings in the postgresql.conf. Any
> ideas or is this the expected speed?

Hmm.

- You asked to update 4,889,820 records.

- It's a table consisting of 8.5GB of data (based on the cost info)

For this to take 15 minutes doesn't seem particularly outrageous.
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