Обсуждение: proposal: use errcontext for custom exception too

Hello

There are small issue in PL/pgSQL and custom exceptions. Custom
exception doesn't set a CONTEXT field. I propose change this behave
for WARNING or EXCEPTION level. The goal is same behave for custom
exception and builtin exception and it can help to identify a RAISE
statement that is responsible to exception.


./pl_exec.c
*** ./pl_exec.c.orig    2011-11-24 17:29:08.000000000 +0100
--- ./pl_exec.c    2011-11-24 18:23:51.513136718 +0100
***************
*** 2827,2833 ****
      /*
       * Throw the error (may or may not come back)
       */
!     estate->err_text = raise_skip_msg;    /* suppress traceback of raise */

      ereport(stmt->elog_level,
              (err_code ? errcode(err_code) : 0,
--- 2827,2834 ----
      /*
       * Throw the error (may or may not come back)
       */
!     if (stmt->elog_level < WARNING)
!         estate->err_text = raise_skip_msg;    /* suppress traceback of raise notice */

      ereport(stmt->elog_level,
              (err_code ? errcode(err_code) : 0,

Regards

Pavel Stehule

On Thu, Nov 24, 2011 at 12:30 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> There are small issue in PL/pgSQL and custom exceptions. Custom
> exception doesn't set a CONTEXT field. I propose change this behave
> for WARNING or EXCEPTION level. The goal is same behave for custom
> exception and builtin exception and it can help to identify a RAISE
> statement that is responsible to exception.

That seems completely arbitrary.  I think we discussed before
providing an option to allow the user to control this, which seems
better than implementing some hardcoded rule that may or may not be
what a given user wants.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

2011/11/25 Robert Haas <robertmhaas@gmail.com>:
> On Thu, Nov 24, 2011 at 12:30 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>> There are small issue in PL/pgSQL and custom exceptions. Custom
>> exception doesn't set a CONTEXT field. I propose change this behave
>> for WARNING or EXCEPTION level. The goal is same behave for custom
>> exception and builtin exception and it can help to identify a RAISE
>> statement that is responsible to exception.
>
> That seems completely arbitrary.  I think we discussed before
> providing an option to allow the user to control this, which seems
> better than implementing some hardcoded rule that may or may not be
> what a given user wants.

A some option via #option or GUC has sense for lower levels like
NOTICE or WARNING. For exception level CONTEXT should be filled every
time - usually you have a stack of CONTEXT calls, because exception
must not be on direct call, but the last CONTEXT (where exception was
created missing). It is confusing. When a advanced developer see a
exception without CONTEXT, then he know so exception is related to
RAISE statement, but still is not simple find a statement, that raised
exception - the line number is missing.

Compromise solution can be GUC where CONTEXT is default for ERROR level

like plpgsql.log_context_error_level = ERROR

A new option on RAISE STATEMENT is not well, usually you want to same
behave on complete application.

Regards

Pavel

>
> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>

On Fri, Nov 25, 2011 at 1:14 AM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> A some option via #option or GUC has sense for lower levels like
> NOTICE or WARNING.

I think what we discussed before was adding some bit of optional
syntax to RAISE that would indicate that the user wants CONTEXT
suppressed.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

Robert Haas <robertmhaas@gmail.com> writes:
> On Thu, Nov 24, 2011 at 12:30 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>> There are small issue in PL/pgSQL and custom exceptions. Custom
>> exception doesn't set a CONTEXT field. I propose change this behave
>> for WARNING or EXCEPTION level. The goal is same behave for custom
>> exception and builtin exception and it can help to identify a RAISE
>> statement that is responsible to exception.

> That seems completely arbitrary.  I think we discussed before
> providing an option to allow the user to control this, which seems
> better than implementing some hardcoded rule that may or may not be
> what a given user wants.

Note also that the current behavior *is* what people want; at least,
we have seen no field complaints about the lack of first-level CONTEXT
for RAISE notices, and plenty of complaints from people who think
there's still too much cruft automatically attached to RAISE output.
If anything, what's been requested is a way to suppress even more
context, not a policy decision to force more of it.
        regards, tom lane

2011/11/25 Tom Lane <tgl@sss.pgh.pa.us>:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Thu, Nov 24, 2011 at 12:30 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
>>> There are small issue in PL/pgSQL and custom exceptions. Custom
>>> exception doesn't set a CONTEXT field. I propose change this behave
>>> for WARNING or EXCEPTION level. The goal is same behave for custom
>>> exception and builtin exception and it can help to identify a RAISE
>>> statement that is responsible to exception.
>
>> That seems completely arbitrary.  I think we discussed before
>> providing an option to allow the user to control this, which seems
>> better than implementing some hardcoded rule that may or may not be
>> what a given user wants.
>
> Note also that the current behavior *is* what people want; at least,
> we have seen no field complaints about the lack of first-level CONTEXT
> for RAISE notices, and plenty of complaints from people who think
> there's still too much cruft automatically attached to RAISE output.
> If anything, what's been requested is a way to suppress even more
> context, not a policy decision to force more of it.
>

People usually don't like verbose output in interactive mode in
console. CONTEXT for RAISE NOTICE is not necessary.  If you have a
small functions, then CONTEXT for RAISE EXCEPTION is not necessary
too. But if you have a functions with hundreds lines, then more
informations about origin of exception is welcome. There is workaround
- with one statement function (RAISE stmt wrapper) I have a expected
behave - but it's not clean RAISE EXCEPTION 'some message' is more
readable than PERFORM elog('some message', ..) and log is not too
readable too.

postgres=# SELECT yyy();
CONTEXT:  SQL statement "SELECT xxx()"
PL/pgSQL function "yyy" line 3 at PERFORM

I can understand to motivation decrease verbosity, but there is clean
request "simply identification a source of exception (exception, not
notification)". Some RAISE stmt option should be - but for NOTICE
level NO_CONTEXT is optimal, and for EXCEPTION NO_CONTEXT is
suboptimal. It has sense just for WARNING level.

Regards

Pavel