On 7/6/2007 7:01 PM, Jeff Davis wrote:
> On Wed, 2007-07-04 at 14:31 -0400, Jan Wieck wrote:
>> What I see here is that we are trying to come up with a special case 
>> optimization for mass-deletes. No mass insert or update operations will 
>> benefit from any of this. Do people do mass deletes that much that we 
>> really have to worry about them?
> 
> Why does this not apply to UPDATEs as well? 

I can see how multiple log rows for DELETE might be combined into one 
subscriber side DELETE statement with a WHERE clause using IN (BETWEEN 
would be difficult in the case of multi-column primary keys).

How you intend to do the same for INSERT or UPDATE is unclear to me. As 
said before, there is no SQL statement logging available and even if it 
where, due to MVCC it won't do us any good because Slony does not 
replicate single transactions in their exact commit order. This 
visibility problem is one of the tricky details that killed pgcluster 1. 
I won't let it sneak into Slony.


Jan

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