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From Andreas Korneliussen <Andreas.Kornelius...@Sun.COM>
Subject Re: RowLocation lifetime
Date Mon, 14 Nov 2005 09:14:17 GMT
Suresh Thalamati wrote:
> Andreas Korneliussen wrote:
> 
>> Mike Matrigali wrote:
>>
> 
> <snip>
> 
> 
>> I would think there are multiple ways of adressing this issue:
>>
>> 1 We could  make the store graciously handle the situation if the 
>> RowLocation points to a deleted+purged row, by returning false if the 
>> RowLocation is invalid, (and from the caller we can give an exception)
> 
> 
> 
> This may not be good option, because purged row location  can 
> potentially be used by an another insert from a different
> transaction.
> 

Maybe I misunderstood, however I assumed the RowLocation would not be 
reused as long as there is a table intent lock on the table. Therefore 
the insert from a different transaction would need to use another 
RowLocation.

Mike Matrigali wrote:
> 2) It can be purged (requires at least TABLE IX, ROW X locking)
>        o all physical evidence of the row is removed from table,
>          both internal and external operations on this row will
>          fail.  Only committed deleted rows are purged.
>          Note this will never happen if you have some
>          sort of lock on the row as the requested X lock is
>          always requested in a system only transaction.
>        o the actual RowLocation will not be reused while
>          at least some sort of table level intent lock is held.

--Andreas

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