Getting user who fired a trigger

Anton Nikiforov wrote:

Dear All,
I have made a trigger procedure that logs all table's changes to the
log_table in XML format, but i do need to log a user who did that and
not succsessful with this.
The documentation (including "37.10. Trigger Procedures") give me nothing.
Could somene supply me with a solution or documentation part that i
should read?

Can't remember which part it is, but you want one of:
SELECT CURRENT_USER;
SELECT SESSION_USER;

My trigger function is written in PL/Ruby because i found no way to make
a "table's structure independent function" with PL/pgsql.

And one more question - is there any special type to store XML instead
of text? This question arised from the problem, that i'm planning (and i
do need this) to store all the database updation history and some small
procedures like adding a user will produce from 1 to 10 records in the
log table of text type. So updating of 1 byte will produce kilobytes of
text. So, maybe there is some compact type for XML storing? (i know that
i could pack it and store in zipped or other format, but i would like to
have a search possibility);

Sorry, I don't think I understand. Do you want to store multiple
versions of the same XML document?
Or are you logging changes to non-XML data as XML text (and if so why)?

--
Richard Huxton
Archonet Ltd

Thanks for the replay, Richard.

Richard Huxton wrote:

Anton Nikiforov wrote:

Dear All,
I have made a trigger procedure that logs all table's changes to the
log_table in XML format, but i do need to log a user who did that and
not succsessful with this.
The documentation (including "37.10. Trigger Procedures") give me
nothing.
Could somene supply me with a solution or documentation part that i
should read?

Can't remember which part it is, but you want one of:
SELECT CURRENT_USER;
SELECT SESSION_USER;

test=# SELECT CURRENT_USER;
current_user
--------------
anton
(1 row)

test=# SELECT SESSION_USER;
session_user
--------------
anton
(1 row)

This gives the same output. Looks like i should check this with the real
operatins to understand the difference or RT*M more.

My trigger function is written in PL/Ruby because i found no way to
make a "table's structure independent function" with PL/pgsql.

And one more question - is there any special type to store XML instead
of text? This question arised from the problem, that i'm planning (and
i do need this) to store all the database updation history and some
small procedures like adding a user will produce from 1 to 10 records
in the log table of text type. So updating of 1 byte will produce
kilobytes of text. So, maybe there is some compact type for XML
storing? (i know that i could pack it and store in zipped or other
format, but i would like to have a search possibility);

Sorry, I don't think I understand. Do you want to store multiple
versions of the same XML document?
Or are you logging changes to non-XML data as XML text (and if so why)?

I'm storing XML prepared text in the database in the column of type
text. And the question is - is there some more wise way to do that? Like
column type XML maybe? :)

--
Best regads,
Anton Nikiforov

Anton Nikiforov wrote:

Could somene supply me with a solution or documentation part that i
should read?

Can't remember which part it is, but you want one of:
SELECT CURRENT_USER;
SELECT SESSION_USER;

test=# SELECT CURRENT_USER;
current_user
--------------
anton
(1 row)

test=# SELECT SESSION_USER;
session_user
--------------
anton
(1 row)

This gives the same output. Looks like i should check this with the real
operatins to understand the difference or RT*M more.

Sometimes a function may be running with the permissions of its creator
rather than the user running it. See the CREATE FUNCTION reference for
details.

--
Richard Huxton
Archonet Ltd