On 7/23/14 6:03 PM, John R Pierce wrote:
On 7/23/2014 1:45 PM, Seamus Abshere wrote:
What if we treat atomicity as optional?
atomicity is not and never will be optional in PostgreSQL.
I'm wondering what a minimal definition of upsert could be - possibly
separating concurrency handling out as a (rigorously defined) option for
those who need it.
-- no guarantees, no index required
UPSERT age = 5 INTO dogs WHERE name = 'Jerry';
and if there's several rows with name='Jerry', you'd want to update them
ALL ? if name isn't indexed, this will, as Tom suggests, require a FULL
table scan, and it still will have issues with concurrency
Ah, I was just saying, in terms of correctness, it seems to me that
upsert shouldn't NEED a index to work, just like you don't need an index
on "name" when you say WHERE name = 'Jerry' in SELECTs or INSERTS or
UPDATES.
Appreciate the defense of data integrity in any case!!
Best,
Seamus
--
Seamus Abshere, SCEA
https://github.com/seamusabshere
