Re: Slow update statement

From: Patrick Hatcher <pathat(at)comcast(dot)net>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Slow update statement
Date: 2005-08-08 02:09:04
Message-ID: 42F6BEC0.9090504@comcast.net
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

Sorry went out of town for the weekend. The update did occur, but I
have no idea when it finished.

Here's the actual query and the explain Update:
cdm.bcp_ddw_ck_cus = 12.7 M
cdm.cdm_ddw_customer = 12.8M

explain
update cdm.cdm_ddw_customer
set indiv_fkey = b.indiv_fkey
from cdm.bcp_ddw_ck_cus b
where
cdm.cdm_ddw_customer.cus_nbr = b.cus_num;

Here's the table layout. It's the first time I noticed this, but there
is a PK on the cus_nbr and an index. Does really need to be both and
could this be causing the issue? I thought that if a primary key was
designated, it was automatically indexed.:

CREATE TABLE cdm.cdm_ddw_customer
(
cus_nbr int8 NOT NULL,
ph_home int8,
ph_day int8,
email_adr varchar(255),
name_prefix varchar(5),
name_first varchar(20),
name_middle varchar(20),
name_last varchar(30),
name_suffix varchar(5),
addr1 varchar(40),
addr2 varchar(40),
addr3 varchar(40),
city varchar(25),
state varchar(7),
zip varchar(10),
country varchar(16),
gender varchar(1),
lst_dte date,
add_dte date,
reg_id int4,
indiv_fkey int8,
CONSTRAINT ddwcus_pk PRIMARY KEY (cus_nbr)
)
WITH OIDS;

CREATE INDEX cdm_ddwcust_id_idx
ON cdm.cdm_ddw_customer
USING btree
(cus_nbr);

CREATE TABLE cdm.bcp_ddw_ck_cus
(
cus_num int8,
indiv_fkey int8 NOT NULL
)
WITHOUT OIDS;

Tom Lane wrote:

>Patrick Hatcher <pathat(at)comcast(dot)net> writes:
>
>
>>I'm running an update statement on about 12 million records using the
>>following query:
>>
>>
>
>
>
>>Update table_A
>>set F1 = b.new_data
>>from table_B b
>>where b.keyfield = table_A.keyfield
>>
>>
>
>What does EXPLAIN show for this?
>
>Do you have any foreign key references to table_A from elsewhere?
>
> regards, tom lane
>
>
>

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Tom Lane 2005-08-08 03:48:25 Re: Slow update statement
Previous Message Patrick Hatcher 2005-08-08 02:00:51 Re: Slow update statement