pg.ddx.io  pgsql-admin@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Rui DeSousa <rui@crazybean.net>
To: Sbob <sbob@quadratum-braccas.com>
Cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
Subject: Re: Automatic partition creation?
Date: Wed, 15 Mar 2023 14:20:00 -0400
Message-ID: <F2EE8A8E-FC1F-465F-981F-D7D28A56FE70@crazybean.net> (raw)
In-Reply-To: <001805b4-c039-49b1-344b-9c52016c6f3b@quadratum-braccas.com>
References: <001805b4-c039-49b1-344b-9c52016c6f3b@quadratum-braccas.com>


> On Mar 15, 2023, at 1:24 PM, Sbob <sbob@quadratum-braccas.com> wrote:
> 
> Is it possible to auto create new partitions as needed with declarative partitioning as well?
> 


I’ve created and used the following function to create yearly partitions.  I would just call the function periodical from cron and provide a lead time; i.e. The partition should be there a month before the new year, etc. 


create or replace function dba.add_yearly_partition(_schema name, _table name, _lead_time interval)
  returns boolean
as $body$
declare
  _create_table_template constant text := '
    create table %1$s.%2$s_%3$s
    partition of %1$s.%2$s
    for values from (''%4$s'') to (''%5$s'')
    ;
  ';
  _date timestamp with time zone := now() + _lead_time;
  _is_valid boolean;
  _sql text;
begin
  for _sql in 
    select replace(
        replace(
            pg_get_expr(c.relpartbound, c.oid)
            , 'FOR VALUES FROM'
            ,'select'
          )
        , 'TO'
        , '<= $1 and $1 <'
      )
      || ';'
    from pg_class p
    join pg_namespace ns on ns.oid = p.relnamespace
      and ns.nspname = _schema
    join pg_inherits i on i.inhparent = p.oid
    join pg_class c on c.oid = i.inhrelid
    where p.relname = _table
    order by c.oid desc
  loop
    execute _sql into _is_valid using _date;
    exit when _is_valid;
  end loop;

  if _is_valid is null then
    raise exception 'Failed to identify partitioned table.';
  elsif not _is_valid then
    execute format(_create_table_template
        , _schema
        , _table
        , extract(year from _date)
        , date_trunc('year', _date)
        , date_trunc('year', _date) + '1 year'::interval
      );
  end if;

  return (not _is_valid);
end;
$body$
  language plpgsql
  set search_path = dba
;

view thread (3+ messages)  latest in thread

Message-ID: <F2EE8A8E-FC1F-465F-981F-D7D28A56FE70@crazybean.net>
Permalink:  ../F2EE8A8E-FC1F-465F-981F-D7D28A56FE70@crazybean.net/
Also on:    postgresql.org/message-id/F2EE8A8E-FC1F-465F-981F-D7D28A56FE70@crazybean.net

 · 

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-admin@postgresql.org
  Cc: rui@crazybean.net, sbob@quadratum-braccas.com, pgsql-admin@lists.postgresql.org
  Subject: Re: Automatic partition creation?
  In-Reply-To: <F2EE8A8E-FC1F-465F-981F-D7D28A56FE70@crazybean.net>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox