Message-ID: <4611EFE1.5010400@obviously.com>
Date: Mon, 02 Apr 2007 23:10:41 -0700
From: Bryce Nesbitt <bryce1@obviously.com>
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	rv:1.8.1.2) Gecko/20061107 SUSE/1.1.1-0.1 SeaMonkey/1.1.1
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To: pgsql-sql@postgresql.org
Subject: Very slow DELETE on 4000 rows of 55000 row table
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I've got a DELETE FROM that seems to run forever, pegging the CPU at
100%.  I can't figure out why it's slow.  Any clues?


stage=# EXPLAIN DELETE FROM EG_INVOICE WHERE PERIOD_ID = 1017506;
Index Scan using ix22f7bc70c7de2059 on eg_invoice  (cost=0.00..105.39
rows=3955 width=6)
   Index Cond: (period_id = 1017506)

stage=# select count(*) FROM EG_INVOICE;
55376

stage=# select count(*) FROM EG_INVOICE where PERIOD_ID = 1017506;;
  4603

stage=# \d EG_INVOICE;
              Table "public.eg_invoice"
     Column     |          Type          | Modifiers
----------------+------------------------+-----------
 invoice_id     | integer                | not null
 cso_id         | integer                | not null
 period_id      | integer                | not null
 invoice_number | character varying(192) |
 invoice_date   | date                   |
 plan_name      | character varying(128) |
 invoice_style  | integer                | not null
 account_id     | integer                |
Indexes:
    "eg_invoice_pkey" PRIMARY KEY, btree (invoice_id)
    "invoice_number_idx" btree (invoice_number)
    "ix22f7bc70c7de2059" btree (period_id)
Foreign-key constraints:
    "fk22f7bc70c7de2059" FOREIGN KEY (period_id) REFERENCES
eg_billing_period(period_id)
    "invoice_to_account" FOREIGN KEY (account_id) REFERENCES
eg_account(account_id)
    "invoice_to_cso" FOREIGN KEY (cso_id) REFERENCES eg_cso(cso_id)

stage=# vacuum analyze verbose EG_INVOICE;
...
INFO:  "eg_invoice": scanned 584 of 584 pages, containing 55376 live
rows and 0 dead rows; 3000 rows in sample, 55376 estimated total rows

PostgreSQL 8.1.8 on i686-redhat-linux-gnu, compiled by GCC gcc (GCC)
4.1.1 20070105 (Red Hat 4.1.1-51)


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