capturing and storing query statement with rules

Started by Andrew Gouldover 22 years ago12 messages
#1Andrew Gould
andrewgould@yahoo.com

I would like to create a audit log of update and
delete queries against a table. I want the log on the
server side, since access will be done using various
clients via ODBC. I would like to capture the user,
current datetime and the query statement. My thought
was to accomplish this by creating a rule that will
insert the information into a log table.

How can I captures the query statement so that I can
place it in a insert query? Is there a variable in
the server that holds the query statement as a string?

Am I about to go in over my head (again)?

Thanks,

Andrew

#2Joe Conway
mail@joeconway.com
In reply to: Andrew Gould (#1)
Re: capturing and storing query statement with rules

Guillaume LELARGE wrote:

Le Mardi 24 Juin 2003 20:17, Andrew Gould a �crit :

I would like to create a audit log of update and
delete queries against a table. I want the log on the
server side, since access will be done using various
clients via ODBC. I would like to capture the user,
current datetime and the query statement. My thought
was to accomplish this by creating a rule that will
insert the information into a log table.

To be server side, you need to use a trigger and a plpgsql function. On this
page you will find more informations on trigger related functions:
http://www.postgresql.org/docs/view.php?version=7.3&idoc=0&file=plpgsql-trigger.html
Perhaps you can compare OLD and NEW rows to know which rows will be updated.
And you'll find at the end of the page how to get current user (current_user
keyword) and current datetime (function now).

How can I captures the query statement so that I can
place it in a insert query? Is there a variable in
the server that holds the query statement as a string?

I think this shows how to do what you want:
http://archives.postgresql.org/pgsql-sql/2003-05/msg00301.php

HTH,

Joe

#3Mike Mascari
mascarm@mascari.com
In reply to: Joe Conway (#2)
Re: capturing and storing query statement with rules

Joe Conway wrote:

Guillaume LELARGE wrote:

Le Mardi 24 Juin 2003 20:17, Andrew Gould a �crit :

I would like to create a audit log of update and
delete queries against a table. I want the log on the
server side, since access will be done using various
clients via ODBC. I would like to capture the user,
current datetime and the query statement. My thought
was to accomplish this by creating a rule that will
insert the information into a log table.

And you'll find at the end of the page how to get current user
(current_user keyword) and current datetime (function now).

How can I captures the query statement so that I can
place it in a insert query? Is there a variable in
the server that holds the query statement as a string?

I think this shows how to do what you want:
http://archives.postgresql.org/pgsql-sql/2003-05/msg00301.php

Maybe debug_query_string should be mapped into a variable like
CURRENT_USER? Perhaps something like CURRENT_QUERY?

Mike Mascari
mascarm@mascari.com

#4Joe Conway
mail@joeconway.com
In reply to: Mike Mascari (#3)
Re: [GENERAL] capturing and storing query statement with rules

(moving to HACKERS)

Mike Mascari wrote:

Joe Conway wrote:

I think this shows how to do what you want:
http://archives.postgresql.org/pgsql-sql/2003-05/msg00301.php

Maybe debug_query_string should be mapped into a variable like
CURRENT_USER? Perhaps something like CURRENT_QUERY?

I was thinking something similar. This exact question has come up at
least three times in the last three months. I doubt we'd want a special
keyword like CURRENT_QUERY, but maybe current_query()?

Comments?

Joe

#5Larry Rosenman
ler@lerctr.org
In reply to: Joe Conway (#4)
Re: [GENERAL] capturing and storing query statement with

--On Tuesday, June 24, 2003 14:07:23 -0700 Joe Conway <mail@joeconway.com>
wrote:

(moving to HACKERS)

Mike Mascari wrote:

Joe Conway wrote:

I think this shows how to do what you want:
http://archives.postgresql.org/pgsql-sql/2003-05/msg00301.php

Maybe debug_query_string should be mapped into a variable like
CURRENT_USER? Perhaps something like CURRENT_QUERY?

I was thinking something similar. This exact question has come up at
least three times in the last three months. I doubt we'd want a special
keyword like CURRENT_QUERY, but maybe current_query()?

Comments?

I was thinking the same thing. Currently I use the contrib/dblink supplied
function, but a firstclass, in the default install, version would be nice.

--
Larry Rosenman http://www.lerctr.org/~ler
Phone: +1 972-414-9812 E-Mail: ler@lerctr.org
US Mail: 1905 Steamboat Springs Drive, Garland, TX 75044-6749

#6Mike Benoit
mikeb@netnation.com
In reply to: Andrew Gould (#1)
Re: capturing and storing query statement with rules

http://gborg.postgresql.org/project/tablelog/download/download.php

or

http://gborg.postgresql.org/project/audittrail/download/download.php?branch=devel

I haven't used either, but table_log seems to be one that I may start
using in the near future.

On Tue, 2003-06-24 at 13:17, Andrew Gould wrote:

I would like to create a audit log of update and
delete queries against a table. I want the log on the
server side, since access will be done using various
clients via ODBC. I would like to capture the user,
current datetime and the query statement. My thought
was to accomplish this by creating a rule that will
insert the information into a log table.

How can I captures the query statement so that I can
place it in a insert query? Is there a variable in
the server that holds the query statement as a string?

Am I about to go in over my head (again)?

Thanks,

Andrew

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--
Best Regards,

Mike Benoit
NetNation Communications Inc.
Systems Engineer
Tel: 604-684-6892 or 888-983-6600
---------------------------------------

Disclaimer: Opinions expressed here are my own and not
necessarily those of my employer

#7Guillaume LELARGE
gleu@wanadoo.fr
In reply to: Andrew Gould (#1)
Re: capturing and storing query statement with rules

Le Mardi 24 Juin 2003 20:17, Andrew Gould a écrit :

I would like to create a audit log of update and
delete queries against a table. I want the log on the
server side, since access will be done using various
clients via ODBC. I would like to capture the user,
current datetime and the query statement. My thought
was to accomplish this by creating a rule that will
insert the information into a log table.

To be server side, you need to use a trigger and a plpgsql function. On this
page you will find more informations on trigger related functions:
http://www.postgresql.org/docs/view.php?version=7.3&amp;idoc=0&amp;file=plpgsql-trigger.html
Perhaps you can compare OLD and NEW rows to know which rows will be updated.
And you'll find at the end of the page how to get current user (current_user
keyword) and current datetime (function now).

How can I captures the query statement so that I can
place it in a insert query? Is there a variable in
the server that holds the query statement as a string?

I don't think... or wasn't able to find something like this one in the
documentation.

Regards.

--
Guillaume <!-- http://absfr.tuxfamily.org/ -->.

#8Tom Lane
tgl@sss.pgh.pa.us
In reply to: Joe Conway (#4)
Re: [GENERAL] capturing and storing query statement with rules

Joe Conway <mail@joeconway.com> writes:

I was thinking something similar. This exact question has come up at
least three times in the last three months. I doubt we'd want a special
keyword like CURRENT_QUERY, but maybe current_query()?

Not unless you want to promote a quick debugging hack, not expected or
required to work 100%, into a supported feature. I don't think
debug_query_string can be relied on to always reflect what the system
is doing, particularly not in the 3.0 protocol extended-query case.
And how about when you're executing queries inside a function --- is it
supposed to tell you about the most closely nested SQL query?

I don't say this is not worth doing --- but I do say you are opening a
larger can of worms than you probably think.

regards, tom lane

#9Joe Conway
mail@joeconway.com
In reply to: Tom Lane (#8)
Re: [GENERAL] capturing and storing query statement with

Tom Lane wrote:

Joe Conway <mail@joeconway.com> writes:

I was thinking something similar. This exact question has come up at
least three times in the last three months. I doubt we'd want a special
keyword like CURRENT_QUERY, but maybe current_query()?

Not unless you want to promote a quick debugging hack, not expected or
required to work 100%, into a supported feature. I don't think
debug_query_string can be relied on to always reflect what the system
is doing, particularly not in the 3.0 protocol extended-query case.
And how about when you're executing queries inside a function --- is it
supposed to tell you about the most closely nested SQL query?

I don't say this is not worth doing --- but I do say you are opening a
larger can of worms than you probably think.

Hmmm. Good points. This one may best wait for 7.5 at least. Does it make
sense to turn it into a TODO?

* promote debug_query_string into a documented, supported feature

Anyone who *does* use the function from dblink, please be sure to report
circumstances where dblink_current_query() returns something other than
what you would expect.

Thanks,

Joe

#10Bruce Momjian
pgman@candle.pha.pa.us
In reply to: Joe Conway (#9)
Re: [GENERAL] capturing and storing query statement with

Added to TODO:

* Promote debug_query_string into a server-side function
current_query()

---------------------------------------------------------------------------

Joe Conway wrote:

Tom Lane wrote:

Joe Conway <mail@joeconway.com> writes:

I was thinking something similar. This exact question has come up at
least three times in the last three months. I doubt we'd want a special
keyword like CURRENT_QUERY, but maybe current_query()?

Not unless you want to promote a quick debugging hack, not expected or
required to work 100%, into a supported feature. I don't think
debug_query_string can be relied on to always reflect what the system
is doing, particularly not in the 3.0 protocol extended-query case.
And how about when you're executing queries inside a function --- is it
supposed to tell you about the most closely nested SQL query?

I don't say this is not worth doing --- but I do say you are opening a
larger can of worms than you probably think.

Hmmm. Good points. This one may best wait for 7.5 at least. Does it make
sense to turn it into a TODO?

* promote debug_query_string into a documented, supported feature

Anyone who *does* use the function from dblink, please be sure to report
circumstances where dblink_current_query() returns something other than
what you would expect.

Thanks,

Joe

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  pgman@candle.pha.pa.us               |  (610) 359-1001
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#11Peter Eisentraut
peter_e@gmx.net
In reply to: Joe Conway (#4)
Re: [GENERAL] capturing and storing query statement with

Joe Conway writes:

I was thinking something similar. This exact question has come up at
least three times in the last three months. I doubt we'd want a special
keyword like CURRENT_QUERY, but maybe current_query()?

The current statement can be examined using the statistics views and
functions.

--
Peter Eisentraut peter_e@gmx.net

#12Tom Lane
tgl@sss.pgh.pa.us
In reply to: Peter Eisentraut (#11)
Re: [GENERAL] capturing and storing query statement with

Peter Eisentraut <peter_e@gmx.net> writes:

Joe Conway writes:

I was thinking something similar. This exact question has come up at
least three times in the last three months. I doubt we'd want a special
keyword like CURRENT_QUERY, but maybe current_query()?

The current statement can be examined using the statistics views and
functions.

That's not very reliable though --- unless the current query has been
running for quite a few milliseconds, there's no guarantee it will be
reflected in the statistics collector's output.

regards, tom lane