Re: Performance Optimization for Dummies 2 - the SQL - Mailing list pgsql-performance

From Carlo Stonebanks
Subject Re: Performance Optimization for Dummies 2 - the SQL
Date
Msg-id eh0u34$cou$1@news.hub.org
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In response to Performance Optimization for Dummies 2 - the SQL  ("Carlo Stonebanks" <stonec.register@sympatico.ca>)
Responses Re: Performance Optimization for Dummies 2 - the SQL
List pgsql-performance
> what is the facility_address_id is null all about? remove it since you
> hardcode it to true in select.

The facility_address_id is null statement is necessary, as this is a
sub-query from a union clause and I want to optimise the query with the
original logic intact. The value is not hard coded to true but rather to
null. Admittedly, it's redundant but I put it there to make sure that I
matched up the columns from the other select in the union clause.

> you have a two part part key on facility(country code, postal code),
> right?

The indexes and constrains are below. If you see redundancy, this was from
vain attempts to please the optimiser gods.

Carlo

ALTER TABLE mdx_core.facility
  ADD CONSTRAINT facility_pkey PRIMARY KEY(facility_id);

CREATE INDEX facility_country_state_city_idx
  ON mdx_core.facility
  USING btree
  (default_country_code, default_state_code, lower(default_city::text));

CREATE INDEX facility_country_state_postal_code_idx
  ON mdx_core.facility
  USING btree
  (default_country_code, default_state_code, default_postal_code);

CREATE INDEX facility_facility_country_state_city_idx
  ON mdx_core.facility
  USING btree
  (facility_id, default_country_code, default_state_code,
lower(default_city::text));

CREATE INDEX facility_facility_country_state_postal_code_idx
  ON mdx_core.facility
  USING btree
  (facility_id, default_country_code, default_state_code,
default_postal_code);


""Merlin Moncure"" <mmoncure@gmail.com> wrote in message
news:b42b73150610161407l55e66854g94b31de6dd511f16@mail.gmail.com...
> On 10/15/06, Carlo Stonebanks <stonec.register@sympatico.ca> wrote:
>> that contains full address data
>> */
>> select
>>     f.facility_id,
>>     null as facility_address_id,
>>     null as address_id,
>>     f.facility_type_code,
>>     f.name,
>>     null as address,
>>     f.default_city as city,
>>     f.default_state_code as state_code,
>>     f.default_postal_code as postal_code,
>>     f.default_country_code as country_code,
>>     null as parsed_unit
>> from
>>     mdx_core.facility as f
>> left outer join mdx_core.facility_address as fa
>>     on fa.facility_id = f.facility_id
>> where
>>      facility_address_id is null
>>      and f.default_country_code = 'US'
>>      and (f.default_postal_code = '14224-1945' or f.default_postal_code =
>> '14224')
>
> what is the facility_address_id is null all about? remove it since you
> hardcode it to true in select.
>
> you have a two part part key on facility(country code, postal code),
> right?
>
> merlin
>
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend
>



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