Just saw these:

#default_transaction_isolation = 'read committed'
#default_transaction_read_only = false

Does the second option control the new read only transaction mode?  I
thought 'read only' was just a new level of transaction isolation (ie. one
of the 4 sql standard ones), so why does it need its own GUC var?

Chris


Mon, 28 Jul 2003 10:39:48 +0800
"Christopher Kings-Lynne" <chriskl@familyhealth.com.au>
new postgresql.conf
On Mon, 28 Jul 2003, Christopher Kings-Lynne wrote:

> Just saw these:
> 
> #default_transaction_isolation = 'read committed'
> #default_transaction_read_only = false
> 
> Does the second option control the new read only transaction mode?  I
> thought 'read only' was just a new level of transaction isolation (ie. one
> of the 4 sql standard ones), so why does it need its own GUC var?

It is a transaction access mode, not an isolation level. ansi sql supports
two modes: read only and read write.

Gavin


Mon, 28 Jul 2003 12:48:40 +1000 (EST)
Gavin Sherry <swm@linuxworld.com.au>
Re: new postgresql.conf
"Christopher Kings-Lynne" <chriskl@familyhealth.com.au> writes:
> Just saw these:
> #default_transaction_isolation = 'read committed'
> #default_transaction_read_only = false
> Does the second option control the new read only transaction mode?

Yes.

> I thought 'read only' was just a new level of transaction isolation (ie. one
> of the 4 sql standard ones), so why does it need its own GUC var?

No, it's orthogonal to isolation.  A read-only transaction could
sensibly want either READ COMMITTED or SERIALIZABLE behavior, depending
on whether it wants to see the effects of commits while it's in progress.

			regards, tom lane

Mon, 28 Jul 2003 01:37:37 -0400
Tom Lane <tgl@sss.pgh.pa.us>
Re: new postgresql.conf 