Обсуждение: How to list ALL PostgreSQL functions?

On Mon, Sep 12, 2016 at 12:46:38PM +0200, Poul Kristensen wrote:
> Sorry for not clear speach!
>
> It seems that all functions have the prefix off  pg_.
>
> I want to list all functions maybe with a short description in the PG api
>
> E.g.
>
> some command listing
>
> pg_last_xlog_receive
> pg_current_xlog_location
> etc.
>
> the \df
> does not help in the case.

Check the docs.

psql \df shows you list of functions.

Description can be found in manual.

Start with:
https://www.postgresql.org/docs/current/static/bookindex.html#AEN182285

and then, click on appropriate function.

For example, link for pg_last_xlog_receive_location is
https://www.postgresql.org/docs/current/static/functions-admin.html#FUNCTIONS-RECOVERY-CONTROL

and pg_current_xlog_location is
https://www.postgresql.org/docs/current/static/functions-admin.html#FUNCTIONS-ADMIN-BACKUP

Best regards,

depesz

On Mon, Sep 12, 2016 at 01:11:11PM +0200, Poul Kristensen wrote:
> Thanks a lot.for links :)
>
> btw:
>
> psql \df gives

\df gives you list of user functions. you can add more parameters, to
limit/extend the list.

like:

\df pg_*

will list all functions (including system one) that start with pg_

\dfS

will list all system functions

\df+ *xlog*

will list all functions (including system) that contain "xlog" in their
name, with some additional columns, which include "description" - one
line info about the function.

Best regards,

depesz

hubert depesz lubaczewski <depesz@depesz.com> writes:
> \df gives you list of user functions. you can add more parameters, to
> limit/extend the list.
> like:
> \df pg_*
> will list all functions (including system one) that start with pg_
> \dfS
> will list all system functions
> \df+ *xlog*
> will list all functions (including system) that contain "xlog" in their
> name, with some additional columns, which include "description" - one
> line info about the function.

Also, you can make your own queries on pg_proc, which is all that psql is
doing here.  A nice abbreviated form is

select oid::regprocedure, obj_description(oid, 'pg_proc') from pg_proc;

which gives you just the name, arg types, and comment for each row.

Keep in mind that

1. This will show you an awful lot of stuff that's not meant to be called
directly from SQL, eg I/O functions, operator implementation functions,
aggregate support functions, cast functions, index support functions.
I count 2831 rows in pg_proc in a virgin installation as of HEAD, and
probably not even 1000 of them are really meant to be called as functions
in ordinary queries.

2. This will not show you some things that look like functions but are
implemented by special grammar productions.  For that you'd have to
look into src/backend/parser/gram.y.

            regards, tom lane

El lun, 12-09-2016 a las 20:00 +0200, Poul Kristensen escribió:
>
> Thanks a lot.
>
> How to size HW resources on a physical server for PG95+?

Please create a new thread and try to avoid mixing subjects 

>
> What does PG95+ like? Cpu? L1(expensive I think) 2 or 3 cache level?.
> RAM?
>
> Any idea?
>
> Thanks
>
> Poul
>
>
>
> 2016-09-12 13:56 GMT+02:00 Tom Lane <tgl@sss.pgh.pa.us>:
> > hubert depesz lubaczewski <depesz@depesz.com> writes:
> > > \df gives you list of user functions. you can add more
> > parameters, to
> > > limit/extend the list.
> > > like:
> > > \df pg_*
> > > will list all functions (including system one) that start with
> > pg_
> > > \dfS
> > > will list all system functions
> > > \df+ *xlog*
> > > will list all functions (including system) that contain "xlog" in
> > their
> > > name, with some additional columns, which include "description" -
> > one
> > > line info about the function.
> >
> > Also, you can make your own queries on pg_proc, which is all that
> > psql is
> > doing here.  A nice abbreviated form is
> >
> > select oid::regprocedure, obj_description(oid, 'pg_proc') from
> > pg_proc;
> >
> > which gives you just the name, arg types, and comment for each row.
> >
> > Keep in mind that
> >
> > 1. This will show you an awful lot of stuff that's not meant to be
> > called
> > directly from SQL, eg I/O functions, operator implementation
> > functions,
> > aggregate support functions, cast functions, index support
> > functions.
> > I count 2831 rows in pg_proc in a virgin installation as of HEAD,
> > and
> > probably not even 1000 of them are really meant to be called as
> > functions
> > in ordinary queries.
> >
> > 2. This will not show you some things that look like functions but
> > are
> > implemented by special grammar productions.  For that you'd have to
> > look into src/backend/parser/gram.y.
> >
> >                         regards, tom lane
> >
>
>
> -- 
> Med venlig hilsen / Best regards
> Poul Kristensen
> Linux-OS/Virtualizationexpert and Oracle DBA