Re: [SQL] Re:Create table doesn't always respect atomicity of transactions - Mailing list pgsql-sql

From Bruce Momjian
Subject Re: [SQL] Re:Create table doesn't always respect atomicity of transactions
Date
Msg-id 199909212117.RAA20410@candle.pha.pa.us
Whole thread Raw
In response to Re: [SQL] Re:Create table doesn't always respect atomicity of transactions  (José Soares <jose@sferacarta.com>)
List pgsql-sql
This is fixed this in 6.5.2.

> There's the same problem in v6.5 using temporary tables:
> 
> prova=> begin;
> BEGIN
> prova=> create temporary table prova(a text);
> CREATE
> prova=> insert into prova values('aa');
> INSERT 225134 1
> prova=> rollback;
> ABORT
> prova=> create table prova(a text);
> ERROR:  Relation 'prova' already exists
> prova=> drop table prova;
> ERROR:  cannot find attribute 1 of relation pg_temp.17407.0
> prova=>
> 
> 
> Mark Dalphin ha scritto:
> 
> > Hi,
> >
> > Running version 6.4.2 of Postgresql on IRIX, I see exactly this same behavior,
> > that is, when I create a table within a transaction and some later action in
> > that transaction generates an error, leaving the transaction in an abort state,
> > leaves me stuck with a ghost table. I can create a new table of the same name
> > because "Table already exists" and I can't delete the table because that table
> > "doesn't exist".
> >
> > I can, however, get around the problem by becoming the Postgres super-user and
> > going into the data/base/...
> > directory; there I find the file with the name of the ghost table (it is of size
> > zero) and I delete it.  The problem then goes away. I assume this bug arises
> > from the order in which Postgres creates entries in its system tables and
> > creates the file on the disk.  As I am not creating tables on the fly, the bug
> > only bites me when I am creating a new DB.
> >
> > In short, I can confirm the behavior you are seeing and I believe it occurs on
> > multiple platforms. I can send in code to re-create the problem is people wish.
> >
> > Mark
> >
> > ----------------------
> > Zalman Stern wrote:
> >
> > > Date: Mon, 21 Jun 1999 22:21:48 -0700 (PDT)
> > > From: Zalman Stern
> > > Subject: Create table doesn't always respect atomicity of transactions.
> > >
> > > Off and on, I've been seeing a situation where the following code:
> > >         begin;
> > >         create table foo (name text);
> > >         abort; leaves a file called "foo" in the database directory and
> > > further attempts to create a relation called foo or to select anything from
> > > it all fail.  The database has been left in an inconsistent state.
> > >
> > > I filed a bug report on this earlier today as it seemed dead on repeatable.
> > > But then I recompiled with debug symbols to have a go at figuring out what
> > > was up and the problem went away. So I recompiled with full optimization
> > > again and the problem still doesn't occur now. I've been starting over each
> > > time with a fresh database so if it was some property of the database
> > > itself, then that state is lost. But this is not the first time I've seen
> > > this. Has any one else seen such a thing? Its rather troublesome 'cause when
> > > it does happen, the database is somewhat unuseable until I remove the file
> > > in question and I hate going in and removing files that are supposed to be
> > > under Postgres' control...
> > >
> > >
> > --
> > Mark Dalphin                          email: mdalphin@amgen.com
> > Mail Stop: 29-2-A                     phone: +1-805-447-4951 (work)
> > One Amgen Center Drive                       +1-805-375-0680 (home)
> > Thousand Oaks, CA 91320                 fax: +1-805-499-9955 (work)
> 
> --
> ______________________________________________________________
> PostgreSQL 6.5.0 on i586-pc-linux-gnu, compiled by gcc 2.7.2.3
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> Jose'
> 
> 
> 
> 


--  Bruce Momjian                        |  http://www.op.net/~candle maillist@candle.pha.pa.us            |  (610)
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