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* PL/Pgsql trigger function problem.
@ 2003-02-08 17:35 James C. Ousley <arcpro@digitalwizardry.net>
0 siblings, 0 replies; 3+ messages in thread
From: James C. Ousley @ 2003-02-08 17:35 UTC (permalink / raw)
To: pgsql-sql
This is suppose to pull all the columns of the table that initiated the trigger func from the sys catalogs, loop through them and put everything that has changed between OLD and NEW into a comma delimited string for input into a log like table for future analysis via middleware (php,perl..,etc). Here is the problem, OLD.A results in 'old does not have field A', which is true. I cant get the OLD and NEW record objects to realize that I want OLD.<string value of A> for the column name instead of an explicit A as the column name. The only way I can find to make this work is by using TCL for the procedural language because of the way it casts the OLD and NEW into an associative array instead of a RECORD object, but by using TCL I will lose functionallity in the "complete" version of the following function which has been stripped to show my specific problem so using TCL is currently not in my list of options. Any insight will be greatly appreciated.
create or replace function hmm() returns TRIGGER as '
DECLARE
table_cols RECORD;
attribs VARCHAR;
A VARCHAR;
BEGIN
IF TG_OP = ''UPDATE'' THEN
FOR table_cols IN select attname from pg_attribute where attrelid = TG_RELID and attnum > -1 LOOP
A := table_cols.attname;
IF OLD.A != NEW.A THEN --Begin problem
IF attribs != '''' THEN
attribs := attribs || '','' || table_cols.attname || ''='' || OLD.A || ''->'' || NEW.A;
ELSE
attribs := table_cols.attname || ''='' || OLD.A || ''->'' || NEW.A;
END IF;
END IF;
END LOOP;
END IF;
RAISE EXCEPTION ''%'', attribs;
RETURN NULL;
END;
' Language 'plpgsql';
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: PL/Pgsql trigger function problem.
@ 2003-02-12 13:48 Christoph Haller <ch@rodos.fzk.de>
0 siblings, 1 reply; 3+ messages in thread
From: Christoph Haller @ 2003-02-12 13:48 UTC (permalink / raw)
To: pgsql-sql; +Cc: arcpro@digitalwizardry.net
>
> This is suppose to pull all the columns of the table that initiated
the t=
> rigger func from the sys catalogs, loop through them and put
everything tha=
> t has changed between OLD and NEW into a comma delimited string for
input i=
> nto a log like table for future analysis via middleware
(php,perl..,etc). =
> Here is the problem, OLD.A results in 'old does not have field A',
which is=
> true. I cant get the OLD and NEW record objects to realize that I
want OLD=
> .<string value of A> for the column name instead of an explicit A as
the co=
> lumn name. The only way I can find to make this work is by using TCL
for t=
> he procedural language because of the way it casts the OLD and NEW
into an =
> associative array instead of a RECORD object, but by using TCL I will
lose =
> functionallity in the "complete" version of the following function
which ha=
> s been stripped to show my specific problem so using TCL is currently
not i=
> n my list of options. Any insight will be greatly appreciated.
>
> create or replace function hmm() returns TRIGGER as '
> DECLARE
> table_cols RECORD;
> attribs VARCHAR;
> A VARCHAR;
> BEGIN
> IF TG_OP =3D ''UPDATE'' THEN
> FOR table_cols IN select attname from pg_attribute where attrelid
=3D =
> TG_RELID and attnum > -1 LOOP
> A :=3D table_cols.attname;
> IF OLD.A !=3D NEW.A THEN --Begin problem=20
> IF attribs !=3D '''' THEN
> attribs :=3D attribs || '','' || table_cols.attname || ''=3D''
|| OL=
> D.A || ''->'' || NEW.A;
> ELSE
> attribs :=3D table_cols.attname || ''=3D'' || OLD.A || ''->''
|| NEW=
> .A;
> END IF;
> END IF;
> END LOOP;
> END IF;
> RAISE EXCEPTION ''%'', attribs;
> RETURN NULL;
> END;
> ' Language 'plpgsql';
>
James,
If I understand your intentions correctly, you are trying to achieve a
general procedure
to log all updates of all tables. Right?
The only way I can think of from my point of knowledge is use middleware
to generate
a big sql script with a CREATE PROCEDURE and CREATE TRIGGER statement
for every table you want updates being logged. This might be no option
for you as well,
but I would like to hear if at least my interpretation of your request
was correct.
Regards, Christoph
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: PL/Pgsql trigger function problem.
@ 2003-02-12 14:59 Jr. <arcpro@digitalwizardry.net>
parent: Christoph Haller <ch@rodos.fzk.de>
0 siblings, 0 replies; 3+ messages in thread
From: Jr. @ 2003-02-12 14:59 UTC (permalink / raw)
To: pgsql-sql
Christopher
Your interpretation of my context is correct. I am using postgresql as
the data warehouse for a user management interface (which utilizes perl
and php) that is tracking everything from customer email accounts to web
hosting. Using multiple logins based off the users real name via a
staff table, ex userid of jsmith has a database user of "John Smith".
By doing this, in conjunction with my current pl/pgsql function I am
able to create a "touchlog" to track what each users do to the various
account information tables with one function and triggers on the tables
that wish tracking to be implemented. I am, as my code showed,
attempting to make it more dynamic by using the system catalogs to
retrieve column names. This way I can maximize the scalability of the
function and do checks of what was changed (or added without recoding
the function when a new service is added) and log it (which I am
currently hard coding certain checks for billable actions but would want
all of the changes logged in an ideal environment). And again with the
way that TCL casts the OLD and NEW into an array I think I could
probably accomplish it with TCL. But if my interpretation of the docs
are correct by using TCL I may loose some functionality that I am
currently using. I am porting my pl/pgsql function to TCL to see exactly
where it may lead, I will post back my results of that experiment at a
later time. Below I have included an example output of the log table so
you can see what I am doing (note: the searches are added via middle
ware. And there is another 'action' that I have to add into the
middleware which is OPEN, because sometimes people do searches but never
do anything else, and I need to know if they look at any account that
was found in their search results. CT-Notes means they added a note
bound to that account but the account did not require a modification, ie
someone forgot their password and we had to look it up, verify who they
were and give it back to them). I think that about sums it up. Thanks
for the point of view as it may very well be the way I may have to do it.
uac=# select * from touchlog where modtime between '2003-02-11' and
'2003-02-12';
id | username | tablename | recid |
modtime | action | attributes
--------+-----------------+-----------+------------+-------------------------------+--------+--------------------------------------------------------------------
766681 | John Smith | customers | | 2003-02-11
00:21:38.608865-05 | SEARCH | username e <username> and domain c
<domain>.net
766682 | John Smith | email | 134463 | 2003-02-11
00:25:18.964397-05 | UPDATE | CT-Notes
766686 | Kris Smith | customers | | 2003-02-11
00:49:34.156166-05 | SEARCH | username c <username> and lname c
766687 | Darren Smith | customers | | 2003-02-11
00:54:56.762122-05 | SEARCH | username c <username> and lname c
766688 | Kris Smith | email | 134463 | 2003-02-11
00:57:31.345123-05 | UPDATE | CT-Notes
766689 | Darren Smith | email | 130537 | 2003-02-11
00:59:42.194031-05 | UPDATE | CT-Notes
766707 | Freda Smith | dsl | 3240 | 2003-02-11
07:40:38.071053-05 | INSERT |
766708 | Freda Smith | email | 84241 | 2003-02-11
07:41:06.038679-05 | UPDATE | plan+Plan A->PLAN_DSL_768+Customer
Name+<domain>.net
766710 | Freda Smith | dialup | 127415 | 2003-02-11
07:41:18.170302-05 | DELETE | 1020772+<username>+<domain>.net+<pop location>
>James,
>If I understand your intentions correctly, you are trying to achieve a
>general procedure
>to log all updates of all tables. Right?
>The only way I can think of from my point of knowledge is use middleware
>to generate
>a big sql script with a CREATE PROCEDURE and CREATE TRIGGER statement
>for every table you want updates being logged. This might be no option
>for you as well,
>but I would like to hear if at least my interpretation of your request
>was correct.
>Regards, Christoph
>
>
>
>
>
>
^ permalink raw reply [nested|flat] 3+ messages in thread
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2003-02-08 17:35 PL/Pgsql trigger function problem. James C. Ousley <arcpro@digitalwizardry.net>
2003-02-12 13:48 Re: PL/Pgsql trigger function problem. Christoph Haller <ch@rodos.fzk.de>
2003-02-12 14:59 ` Jr. <arcpro@digitalwizardry.net>
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