Re: Progress of asynchronous queries

[Adriaan van Os <postgres(at)microbizz(dot)nl>]

Jeroen T. Vermeulen wrote:
> Adriaan van Os wrote:
>
> > Besides, when more than one user is connected, multiple SQL commands may
> > behave different than a
> > single SQL command
> > (<http://www.postgresql.org/docs/8.1/static/transaction-iso.html>)
>
> But you'd be doing this in a transaction anyway: you can't declare a
> cursor without starting a transaction first.Yes, you could deliberately
> declare "WITH HOLD" and keep using your cursor after commiting or aborting
> the transaction.  But even then, so far as I know, the cursor presents a
> snapshot view of its result set so you get an effective isolation level of
> "serializable" even then.

No, carefully read <http://www.postgresql.org/docs/8.1/static/transaction-iso.html>.

> The number of users has nothing to do with the matter

It does.

> if that were a real
> concern, you'd be using a serializable transaction anyway, so you wouldn't
> have to worry about it even if cursors did behave as "read committed."

I don't want to be forced to use serializable transaction mode, just because I want to know the 
progress of an SQL command.

Regards,

Adriaan van Os