| From: | Greg Stark <gsstark(at)mit(dot)edu> |
|---|---|
| To: | Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov> |
| Cc: | Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>, drkp(at)csail(dot)mit(dot)edu, pgsql-hackers(at)postgresql(dot)org, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Subject: | Re: Serializable Snapshot Isolation |
| Date: | 2010-09-25 12:05:17 |
| Message-ID: | AANLkTikBZExgAwe5TifX4eMxFYyK9MKzRL8T+QTD+oAB@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Thu, Sep 23, 2010 at 4:08 PM, Kevin Grittner
<Kevin(dot)Grittner(at)wicourts(dot)gov> wrote:
> One place I'm particularly interested in using such a feature is in
> pg_dump. Without it we have the choice of using a SERIALIZABLE
> transaction, which might fail or cause failures (which doesn't seem
> good for a backup program) or using REPEATABLE READ (to get current
> snapshot isolation behavior), which might capture a view of the data
> which contains serialization anomalies.
I'm puzzled how pg_dump could possibly have serialization anomalies.
Snapshot isolation gives pg_dump a view of the database containing all
modifications committed before it started and no modifications which
committed after it started. Since pg_dump makes no database
modifications itself it can always just be taken to occur
instantaneously before any transaction which committed after it
started.
--
greg
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Michael Haggerty | 2010-09-25 12:28:06 | Congratulations on leaving CVS |
| Previous Message | KaiGai Kohei | 2010-09-25 11:04:15 | Re: security label support, revised |