Re: Capacity questions

On 06/17/2012 11:11 AM, Bill House wrote:
> On 06/17/2012 01:02 PM, Daniele Varrazzo wrote:
>> On Sun, Jun 17, 2012 at 4:32 PM, Bill House <wch-tech(at)house-grp(dot)net> wrote:
>>
>>> I have a written a script which does what I want it to do on a table
>>> with 999 records.
>>>
>>> I was wondering if there is anything I need to consider if I run this
>>> script on a table with 1.1 million records?
>> It looks fine for me. The only note is that, I may be wrong, but
>> "UPDATE %s SET del = False" updates the records having del already
>> false too, taking more time and creating unnecessary bloat. Adding
>> "WHERE del" may help keeping the bloat to the minimum.
>>
>> -- Daniele
>>
>>
> You are referring to the first SQL command, and you are correct. And on
> a table this size, time is a consideration; even if it is a one-time task.

An additional comment:

You really ought to consider using the parameter passing mechanism built into psycopg2:

http://initd.org/psycopg/docs/usage.html#passing-parameters-to-sql-queries

See here for why that is important:

http://blog.endpoint.com/2012/06/detecting-postgres-sql-injection.html

>
> Thanks very much.
>
> Regards,
>
> Bill
>

--
Adrian Klaver
adrian(dot)klaver(at)gmail(dot)com