Date: Tue, 14 Sep 1999 20:22:15 +0200
From: Michael Meskes <meskes@postgreSQL.org>
To: Margarita Barvinok <brita@umich.edu>
Cc: pgsql-interfaces@postgreSQL.org
Subject: Re: [INTERFACES] Transaction: Begin, Lock
Message-ID: <19990914202215.A5414@gmx.net>
Mail-Followup-To: Margarita Barvinok <brita@umich.edu>,
	pgsql-interfaces@postgresql.org
References: <Pine.SOL.4.10.9909131044130.5490-100000@joust.rs.itd.umich.edu>
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In-Reply-To: <Pine.SOL.4.10.9909131044130.5490-100000@joust.rs.itd.umich.edu>;
	from Margarita Barvinok on Mon, Sep 13, 1999 at 10:58:43AM -0400

On Mon, Sep 13, 1999 at 10:58:43AM -0400, Margarita Barvinok wrote:
> EXEC SQL CONNECT TO ...
> for (i=2; i<x: i++) {
>   strncpy(oid_c, entries[i].val, 10);  /* get oid */
>   oid_rec = atoi(oid_c);
>   EXEC SQL BEGIN WORK;
>   EXEC SQL DELETE FROM phonebook
>            WHERE oid = :oid_rec;
>   EXEC SQL COMMIT WORK;
> }
> EXEC SQL DISCONNECT;
> 
> 1. Why i get the following message when I run this code?
> NOTICE: BeginTransactionBlock and not in default state

I take it you did not use 'ecpg -t' did you? The normal situation is that
ecpg creates a auto-transaction mode, i.e. a transaction is started
automatically. You only need to issue a COMMIT once you finish your
transaction resp. a ROLLBACK if you want to cancel it. 

So you tell the backend to start a transaction while already inside a
transaction. And that cannot work. 

You can either just remove the BEGIN WORK statement or you always give
option '-t' to ecpg.

> 2. How should I lock the table phonebook during this transaction?

Why do you need that? You do not need an explicit lock for the delete to
work.

Michael
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