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Date: Fri, 28 Nov 2014 16:54:57 +1100
Subject: Re: Db transactions and locking
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:81668

On Fri, Nov 28, 2014 at 4:44 PM, Frank Millman <frank@chagford.com> wrote:
> There seems to be a difference between conn.commit() and
> cur.execute('commit'), which leaves the connection in a different state.

Yes, if a connection library offers a way to commit/roll back, it's
usually best to use that.

> However, for my purposes, this is academic.
>
> The main lesson I have learned is that you should always issue a commit
> after any logical set of SQL statements, even if they are only SELECTs,
> otherwise the locks are not released.

Correct. Every time you use any database, you should think in terms of
units of work, which correspond precisely to transactions.

ChrisA