Message-ID: <39E4B11C.204A69A3@noao.edu>
Date: Wed, 11 Oct 2000 11:27:40 -0700
From: Steve Wampler <swampler@noao.edu>
Organization: National Solar Observatory
MIME-Version: 1.0
To: Peter Mount <peter@retep.org.uk>
CC: Joseph Shraibman <jks@selectacast.net>,
	"pgsql-interfaces@postgreSQL.org" <pgsql-interfaces@postgresql.org>
Subject: Re: JDBC Large ResultSet problem + BadTimeStamp Patch
References: <Pine.LNX.4.21.0010111901340.8388-100000@maidast.demon.co.uk>
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Peter Mount wrote:
...
> Yes, there is a problem with multiple statements and transactions on the
> same connection when it comes to thread safety.
> 
> The problem as I see it is two fold.
> 
> 1: How to deal with two statements within one transaction. Related to this
> is the metadata methods that issue queries, how to deal with them while
> within a transaction.
> 
> 2: Currently the JDBC Specs only have transactions supported at the
> Connection level, so I can't see how they thought that Statements could
> possibly run within their own transactions, unless they thought that a
> workaround of this is the use of batches.

Ah, that probably explains why I've seen "tuple arrived before metadata"
messages when I've got several apps talking through CORBA to a java app
that connects to postgres.  Do I need to synchronize both inserts and
queries at the java app level to prevent this?  (I was hoping that
the BEGIN/END block in a transaction would be sufficient, but this makes
it sound as though it isn't.)

--
Steve Wampler-  SOLIS Project, National Solar Observatory
swampler@noao.edu