Fields idx_scan and idx_tup_fetch are not changed by an index scan.

    =# create table class1 (id integer);
    CREATE TABLE
    =# 
    -- Insert 0..9999 into class1
    =# create index class1_id_index on class1 (id);
    CREATE INDEX
    =# vacuum analyze;
    VACUUM
    =# \x
    Expanded display is on.
    =# select * from pg_stat_all_tables where relname = 'class1';
    -[ RECORD 1 ]-+-------
    relid         | 17166
    schemaname    | public
    relname       | class1
    seq_scan      | 2
    seq_tup_read  | 13000
    idx_scan      | 0
    idx_tup_fetch | 0
    n_tup_ins     | 10000
    n_tup_upd     | 0
    n_tup_del     | 0

    =# \x
    Expanded display is off.
    =# explain select * from class1 where id = 1234;
				      QUERY PLAN                                  
    ------------------------------------------------------------------------------
     Index Scan using class1_id_index on class1  (cost=0.00..3.01 rows=2 width=4)
       Index Cond: (id = 1234)
    (2 rows)

    =# \x
    Expanded display is on.
    =# select * from pg_stat_all_tables where relname = 'class1';
    -[ RECORD 1 ]-+-------
    relid         | 17166
    schemaname    | public
    relname       | class1
    seq_scan      | 2
    seq_tup_read  | 13000
    idx_scan      | 0
    idx_tup_fetch | 0
    n_tup_ins     | 10000
    n_tup_upd     | 0
    n_tup_del     | 0

    =# 


Kenji Sugita                                      

Sun, 20 Jul 2003 22:12:39 +0900 (JST)
Kenji Sugita <sugita@srapc1327.sra.co.jp>
Index counters of statistics collector does not work on 7.4devel
"Kenji Sugita" <sugita@srapc1327.sra.co.jp> wrote:
>     =# explain select * from class1 where id = 1234;
>       QUERY PLAN
>     ----------------------------------------------------------------------
--------
>      Index Scan using class1_id_index on class1  (cost=0.00..3.01 rows=2
width=4)
>        Index Cond: (id = 1234)
>     (2 rows)

I don't think that the select is really performed, try the same experiment
but doing
explain analyze instead.


Regards
Gaetano Mendola



Sun, 20 Jul 2003 15:42:29 +0200
"Mendola Gaetano" <mendola@bigfoot.com>
Re: Index counters of statistics collector does not work on 7.4devel
From: "Mendola Gaetano" <mendola@bigfoot.com>
Subject: Re: [HACKERS] Index counters of statistics collector does not work on 7.4devel
Date: Sun, 20 Jul 2003 15:42:29 +0200

;;; "Kenji Sugita" <sugita@srapc1327.sra.co.jp> wrote:
;;; >     =# explain select * from class1 where id = 1234;
;;; >       QUERY PLAN
;;; >     ----------------------------------------------------------------------
;;; --------
;;; >      Index Scan using class1_id_index on class1  (cost=0.00..3.01 rows=2
;;; width=4)
;;; >        Index Cond: (id = 1234)
;;; >     (2 rows)
;;; 
;;; I don't think that the select is really performed, try the same experiment
;;; but doing
;;; explain analyze instead.

I forgot to include a select without explain.  I found it July 15. Anyway it
works for today's version.


Kenji Sugita                                      


Sun, 20 Jul 2003 23:38:46 +0900 (JST)
Kenji Sugita <sugita@srapc1327.sra.co.jp>
Re: Index counters of statistics collector does not work