
don't want to bring up a touchy subject, BUT... does the rule system
actually work, and if not, what are our plans?  It would extend the
functionality of postgresql quite a bit and make it much more
attractive..  also I'm working on a modified version of pg with perl
language support.  that's right, perl.  so far I've got it to the
point where you can create perl functions (using anon sub refs) and
access your arguments and perform operations (from pg_operator) on
them.  I'll get the patches together soon, once I add operator
overloading :)

one more thing -- what about making the listen/notify interface
synchronous?  what must be done?  and... and...  select foo[5:] for
elements 5 and onward in array foo..

Tue, 10 Feb 1998 22:41:17 -0800
Brett McCormick <brett@work.chicken.org>
rule system, perl and other good stuff

DOH -- that's another question I meant to ask, as I noticed some
things in the new (6.3) code about it..  no, it isn't, it is hacked in
just like fmgr_dynamic is..  what do I need to know about the create
language interface..  any docs?

On Wed, 11 February 1998, at 14:26:23, Vadim B. Mikheev wrote:

> One question: is your perl language support compatible with
> new dynamic language interface (CREATE LANGUAGE etc) ?
> 
> Vadim

Tue, 10 Feb 1998 23:26:21 -0800
Brett McCormick <brett@work.chicken.org>
Re: [HACKERS] rule system, perl and other good stuff
Brett McCormick wrote:
> 
> don't want to bring up a touchy subject, BUT... does the rule system
> actually work, and if not, what are our plans?  It would extend the
> functionality of postgresql quite a bit and make it much more
> attractive..  also I'm working on a modified version of pg with perl
> language support.  that's right, perl.  so far I've got it to the
> point where you can create perl functions (using anon sub refs) and
> access your arguments and perform operations (from pg_operator) on
> them.  I'll get the patches together soon, once I add operator
> overloading :)

One question: is your perl language support compatible with
new dynamic language interface (CREATE LANGUAGE etc) ?

Vadim

Wed, 11 Feb 1998 14:26:23 +0700
"Vadim B. Mikheev" <vadim@sable.krasnoyarsk.su>
Re: [HACKERS] rule system, perl and other good stuff

I don't see CREATE LANGUAGE in the grammar file...  are you asking if
it is strictly compatible or if it uses the dynamic language interface?
there's no reason it shouldn't be compatible..

On Wed, 11 February 1998, at 14:26:23, Vadim B. Mikheev wrote:

> One question: is your perl language support compatible with
> new dynamic language interface (CREATE LANGUAGE etc) ?
> 
> Vadim

Tue, 10 Feb 1998 23:29:39 -0800
Brett McCormick <brett@work.chicken.org>
Re: [HACKERS] rule system, perl and other good stuff

okay... yes it can co-exist with CREATE LANGUAGE as long as it is
coded into the server like fmgr_dynamic is.  it will not function as a
CREATE LANGUAGE function.  this is because all that this functionality
appears to do is associate a single function with a language.  but it
does not pass the prosrc attribute (or probin for that matter) to the
function, so no matter what you say for as 'insert code here', it
never gets to the function, so the function has no idea what to do!

I must be missing something.

On Tue, 10 February 1998, at 23:29:39, Brett McCormick wrote:

> I don't see CREATE LANGUAGE in the grammar file...  are you asking if
> it is strictly compatible or if it uses the dynamic language interface?
> there's no reason it shouldn't be compatible..
> 
> On Wed, 11 February 1998, at 14:26:23, Vadim B. Mikheev wrote:
> 
> > One question: is your perl language support compatible with
> > new dynamic language interface (CREATE LANGUAGE etc) ?
> > 
> > Vadim

Tue, 10 Feb 1998 23:40:41 -0800
Brett McCormick <brett@work.chicken.org>
Re: [HACKERS] rule system, perl and other good stuff
Brett McCormick wrote:
> 
> I don't see CREATE LANGUAGE in the grammar file...  are you asking if
> it is strictly compatible or if it uses the dynamic language interface?
> there's no reason it shouldn't be compatible..
...
> DOH -- that's another question I meant to ask, as I noticed some
> things in the new (6.3) code about it..  no, it isn't, it is hacked in
> just like fmgr_dynamic is..  what do I need to know about the create
> language interface..  any docs?
...
> okay... yes it can co-exist with CREATE LANGUAGE as long as it is
> coded into the server like fmgr_dynamic is.  it will not function as a
> CREATE LANGUAGE function.  this is because all that this functionality
> appears to do is associate a single function with a language.  but it
> does not pass the prosrc attribute (or probin for that matter) to the
> function, so no matter what you say for as 'insert code here', it
> never gets to the function, so the function has no idea what to do!

Sorry: CREATE PLangTrusted PROCEDURAL LANGUAGE...

PL handler function has to be created (via CREATE FUNCTION)
before language creation..

After that you are able to do something like this (having PL/tcl):

            create function overpaid_2 (EMP)
                returns bool as '        
                    if {200000.0 < $EMP(salary)} {
                        return 't'
                    }                                                
                    if {$EMP(age) < 30 && 100000.0 < $EMP(salary)} { 
                        return 't'                                   
                    }       
                    return 'f'
                ' language 'pltcl';         
                  ^^^^^^^^^^^^^^^^
                           ^^^^^^^ in addition to built-in languages!

Dynamic procedural language interface and support for TCL are
implemented by Jan (wieck@sapserv.debis.de) - please contact to him
to get more info (btw, there is create_language.l)...

It would be nice to have support for perl...

BTW, Mark, I don't see PLtcl in current sources.
It would be nice to have it under contrib/pl or, even better, under
src/pl (may be with flag USE_PLTCL in Makefile - like USE_TCL :), -
with automatical installation into template database by initdb).

Vadim

Wed, 11 Feb 1998 15:19:48 +0700
"Vadim B. Mikheev" <vadim@sable.krasnoyarsk.su>
Re: [HACKERS] rule system, perl and other good stuff
Hi,

>
>
> don't want to bring up a touchy subject, BUT... does the rule system
> actually work, and if not, what are our plans?  It would extend the
> functionality of postgresql quite a bit and make it much more
> attractive..  also I'm working on a modified version of pg with perl
> language support.  that's right, perl.  so far I've got it to the
> point where you can create perl functions (using anon sub refs) and
> access your arguments and perform operations (from pg_operator) on
> them.  I'll get the patches together soon, once I add operator
> overloading :)

    The  rule  system is wired up in some places. Especially it's
    impossible to have the values of the OLD and  NEW  tuples  in
    UPDATE rules. But we have triggers that can do all the things
    rules might do.

    The function and trigger manager  in  6.3  are  prepared  for
    things  like functions in perl. There is a new command CREATE
    PROCEDURAL LANGUAGE.  Look at the create_language manpage for
    details.    Except   for  user  defined  type  input-/output-
    functions anything can  be  done  in  a  procedural  language
    (functions,  triggers,  operators,  aggregates).  It would be
    very nice if your perl support makes use of the  API  defined
    for procedural languages.

    I've already written a call handler for the Tcl language that
    supports functions and  trigger  procedures  written  in  Tcl
    (it's  not  in  the  contrib up to now, mail me if you want a
    developers copy). The  procedural  language  support  of  the
    backend  is  a  result  from  that work. As long as your perl
    stuff isn't able to handle things that cannot be  done  in  C
    right  now (like returning sets), there is absolutely no need
    to patch the backend again.

    And I currently work on a pure PL/pgSQL  handler  independent
    of  other  things  like  perl/Tcl.  This  one  will  also  be
    implemented as a handler for the procedural language support.

>
> one more thing -- what about making the listen/notify interface
> synchronous?  what must be done?  and... and...  select foo[5:] for
> elements 5 and onward in array foo..
>
>

    In   contrast   I  would  vote  for  adding  a  really  async
    functionality of the whole  frontend/backend  protocol.  That
    would  fit much better in the event driven world of graphical
    programs.


Until later, Jan

--

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#======================================== jwieck@debis.com (Jan Wieck) #



Wed, 11 Feb 1998 09:20:59 +0100 (MET)
jwieck@debis.com (Jan Wieck)
Re: [HACKERS] rule system, perl and other good stuff
Vadim wrote:

>
>
> It would be nice to have support for perl...

    Asked for implementers sometimes :-)

>
> BTW, Mark, I don't see PLtcl in current sources.
> It would be nice to have it under contrib/pl or, even better, under
> src/pl (may be with flag USE_PLTCL in Makefile - like USE_TCL :), -
> with automatical installation into template database by initdb).
>
> Vadim
>

    Sure. Let me do some final tests (checking that PL/Tcl in the
    current version works with Tcl7.5 and Tcl8.0  with  the  same
    sources).  Then  I'll  upload  a  tar  for  putting  it  into
    src/pl/pltcl  or  contrib/pl/pltcl  (expecting   the   source
    directory in ../../src).

    There is a little test suite included into the directory.  It
    checks triggers, functions, operators and  aggregates.  Since
    building  is  optional,  I don't think that a real regression
    test is a good idea.

    Time is limited. So the USE_PLTCL part is up to you -  sorry.


Until later, Jan

--

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#======================================== jwieck@debis.com (Jan Wieck) #



Wed, 11 Feb 1998 09:45:21 +0100 (MET)
jwieck@debis.com (Jan Wieck)
Re: [HACKERS] rule system, perl and other good stuff
>     Sure. Let me do some final tests (checking that PL/Tcl in the
>     current version works with Tcl7.5 and Tcl8.0  with  the  same
>     sources).  Then  I'll  upload  a  tar  for  putting  it  into
>     src/pl/pltcl  or  contrib/pl/pltcl  (expecting   the   source
>     directory in ../../src).

    Ment ../../../src :-)

-- 

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#======================================== jwieck@debis.com (Jan Wieck) #


Wed, 11 Feb 1998 09:47:32 +0100 (MET)
jwieck@debis.com (Jan Wieck)
Re: [HACKERS] rule system, perl and other good stuff
Jan Wieck wrote:
> 
>     Sure. Let me do some final tests (checking that PL/Tcl in the
>     current version works with Tcl7.5 and Tcl8.0  with  the  same
>     sources).  Then  I'll  upload  a  tar  for  putting  it  into
>     src/pl/pltcl  or  contrib/pl/pltcl  (expecting   the   source
>     directory in ../../src).

Nice!

> 
>     There is a little test suite included into the directory.  It
>     checks triggers, functions, operators and  aggregates.  Since
>     building  is  optional,  I don't think that a real regression
>     test is a good idea.

Nice2!!

> 
>     Time is limited. So the USE_PLTCL part is up to you -  sorry.

...Up to Mark (?) - sorry -:)

Vadim

Wed, 11 Feb 1998 15:57:13 +0700
"Vadim B. Mikheev" <vadim@sable.krasnoyarsk.su>
Re: [HACKERS] rule system, perl and other good stuff
>
>
> okay... yes it can co-exist with CREATE LANGUAGE as long as it is
> coded into the server like fmgr_dynamic is.  it will not function as a
> CREATE LANGUAGE function.  this is because all that this functionality
> appears to do is associate a single function with a language.  but it
> does not pass the prosrc attribute (or probin for that matter) to the
> function, so no matter what you say for as 'insert code here', it
> never gets to the function, so the function has no idea what to do!
>
> I must be missing something.

    Think  so.  Using the dynamic language interface, the handler
    is called by fmgr_pl() and one of the arguments is the Oid of
    the  called  PL  function.  So the handler has to do a system
    cache lookup  on  pg_proc  (at  least  the  first  time  this
    function is called) to get the prosrc attribute. The AS '...'
    text on CREATE FUNCTION  will  be  found  there  for  dynamic
    languages.  It's  handler  specific  what  it expects in this
    attribute. For PL/Tcl it's the procedures body and it  builds
    a  Tcl  proc around it after analyzing pg_proc and some other
    system catalogs. The Tcl proc's name  contains  the  Oid,  so
    overloading  functions with different parameter types isn't a
    problem.

    A few minutes ago I sent down the PL/Tcl  directory  to  this
    list.  Look at it and reuse anything that might help to build
    PL/perl.  I really hope that PL/perl and PL/Tcl appear in the
    6.3 distribution. I'll do whatever I can to make this happen.

>
> On Tue, 10 February 1998, at 23:29:39, Brett McCormick wrote:
>
> > I don't see CREATE LANGUAGE in the grammar file...  are you asking if
> > it is strictly compatible or if it uses the dynamic language interface?
> > there's no reason it shouldn't be compatible..
> >
> > On Wed, 11 February 1998, at 14:26:23, Vadim B. Mikheev wrote:
> >
> > > One question: is your perl language support compatible with
> > > new dynamic language interface (CREATE LANGUAGE etc) ?
> > >
> > > Vadim
>
>


Until later, Jan

--

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#======================================== jwieck@debis.com (Jan Wieck) #



Wed, 11 Feb 1998 10:25:44 +0100 (MET)
jwieck@debis.com (Jan Wieck)
Re: [HACKERS] rule system, perl and other good stuff

I certainly was.  It should be easy to switch over to using the
dynamic PL mechanism.  I hope to investing some time into it into the
next few weeks to get it up to snuff.  It will accept a package
function or an anonymous sub ref as the AS clause src.  Strings and
integers are passed as scalars, and everything else is passed as a
Postgres::Type.  I was debating whether to make them
Postgres::Type::datetime (to add type-specific methods in .pm files?)
A scalar, array or Postgres::Type can be returned and will be cast
automatically (if need be).

On Wed, 11 February 1998, at 10:25:44, Jan Wieck wrote:

> 
>     Think  so.  Using the dynamic language interface, the handler
>     is called by fmgr_pl() and one of the arguments is the Oid of
>     the  called  PL  function.  So the handler has to do a system
>     cache lookup  on  pg_proc  (at  least  the  first  time  this
>     function is called) to get the prosrc attribute. The AS '...'
>     text on CREATE FUNCTION  will  be  found  there  for  dynamic
>     languages.  It's  handler  specific  what  it expects in this
>     attribute. For PL/Tcl it's the procedures body and it  builds
>     a  Tcl  proc around it after analyzing pg_proc and some other
>     system catalogs. The Tcl proc's name  contains  the  Oid,  so
>     overloading  functions with different parameter types isn't a
>     problem.
> 
>     A few minutes ago I sent down the PL/Tcl  directory  to  this
>     list.  Look at it and reuse anything that might help to build
>     PL/perl.  I really hope that PL/perl and PL/Tcl appear in the
>     6.3 distribution. I'll do whatever I can to make this happen.
> 
> >
> > On Tue, 10 February 1998, at 23:29:39, Brett McCormick wrote:
> >
> > > I don't see CREATE LANGUAGE in the grammar file...  are you asking if
> > > it is strictly compatible or if it uses the dynamic language interface?
> > > there's no reason it shouldn't be compatible..
> > >
> > > On Wed, 11 February 1998, at 14:26:23, Vadim B. Mikheev wrote:
> > >
> > > > One question: is your perl language support compatible with
> > > > new dynamic language interface (CREATE LANGUAGE etc) ?
> > > >
> > > > Vadim
> >
> >
> 
> 
> Until later, Jan
> 
> --
> 
> #======================================================================#
> # It's easier to get forgiveness for being wrong than for being right. #
> # Let's break this rule - forgive me.                                  #
> #======================================== jwieck@debis.com (Jan Wieck) #
> 
> 

Wed, 11 Feb 1998 01:38:08 -0800
Brett McCormick <brett@work.chicken.org>
Re: [HACKERS] rule system, perl and other good stuff
BTW,

    recently  I  hacked  around on the SETUID stuff and it wasn't
    that much to do.

    I renamed the obsolete and unsupported proistrusted attribute
    in pg_proc to proissetuid and made it default to false.  Then
    I   hacked   some   code    into    ExecMakeFunctionResult(),
    ExecCallTriggerFunc()  and  utils/init/miscinit.c and voila -
    setting proissetuid to true works for 'sql', 'C', and any  PL
    functions called via a func node by the executor or triggerd.
    It does not work for input/output  functions  and  I  haven't
    checked  about  operators  and aggregates. I don't think that
    types  input/output   functions   need   it   and   for   the
    operators/aggregates it must be that easy too.

    What should the syntax for setting/unsetting proissetuid?

        ALTER FUNCTION funcname (args) (NO)SETUID

    looks good for me.

    But before doing anything here I think we should also be able
    to make a view setuid. I haven't thought much about  that  up
    to now.  Any ideas how and where this could be done?


Until later, Jan

--

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#======================================== jwieck@debis.com (Jan Wieck) #



Wed, 11 Feb 1998 10:41:27 +0100 (MET)
jwieck@debis.com (Jan Wieck)
Re: [HACKERS] rule system, perl and other good stuff
On Wed, 11 Feb 1998, Jan Wieck wrote:
 
>     A few minutes ago I sent down the PL/Tcl  directory  to  this
>     list.  Look at it and reuse anything that might help to build
>     PL/perl.  I really hope that PL/perl and PL/Tcl appear in the
>     6.3 distribution. I'll do whatever I can to make this happen.

	Hrmmmm...I always love these "blanket" invitations :)

	I've installed it as src/pl/tcl...


Wed, 11 Feb 1998 09:08:58 -0500 (EST)
The Hermit Hacker <scrappy@hub.org>
Re: [HACKERS] rule system, perl and other good stuff
> 
> On Wed, 11 Feb 1998, Jan Wieck wrote:
>  
> >     A few minutes ago I sent down the PL/Tcl  directory  to  this
> >     list.  Look at it and reuse anything that might help to build
> >     PL/perl.  I really hope that PL/perl and PL/Tcl appear in the
> >     6.3 distribution. I'll do whatever I can to make this happen.
> 
> 	Hrmmmm...I always love these "blanket" invitations :)
> 
> 	I've installed it as src/pl/tcl...
> 
> 


    CVSup'd that - but where's the test subdirectory gone?

Jan


-- 

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#======================================== jwieck@debis.com (Jan Wieck) #


Wed, 11 Feb 1998 15:28:08 +0100 (MET)
jwieck@debis.com (Jan Wieck)
Re: [HACKERS] rule system, perl and other good stuff
On Wed, 11 Feb 1998, Jan Wieck wrote:

> > 
> > On Wed, 11 Feb 1998, Jan Wieck wrote:
> >  
> > >     A few minutes ago I sent down the PL/Tcl  directory  to  this
> > >     list.  Look at it and reuse anything that might help to build
> > >     PL/perl.  I really hope that PL/perl and PL/Tcl appear in the
> > >     6.3 distribution. I'll do whatever I can to make this happen.
> > 
> > 	Hrmmmm...I always love these "blanket" invitations :)
> > 
> > 	I've installed it as src/pl/tcl...
> > 
> > 
> 
> 
>     CVSup'd that - but where's the test subdirectory gone?

	Check it again?  I just checked here, and its been
committed...yup, just checked the physical CVSROOT directories, and they
are there too...

Marc G. Fournier                                
Systems Administrator @ hub.org 
primary: scrappy@hub.org           secondary: scrappy@{freebsd|postgresql}.org 


Wed, 11 Feb 1998 21:28:16 -0400 (AST)
The Hermit Hacker <scrappy@hub.org>
Re: [HACKERS] rule system, perl and other good stuff