simultaneous multiple requests to very simple database

[Eric S. Johansson]

Robert Brewer wrote:
> Eric S. Johansson wrote:
> 
>>I have an application where I need a very simple database, 
>>effectively a very large dictionary.  The very large
>>dictionary must be accessed from multiple processes
>>simultaneously.  I need to be able to lock records within
>>the very large dictionary when records are written to.
> 
> 
> Just to clarify, you want shared-read until a write, at which point you
> want to lock just the item being written? Or would page or table locking
> be acceptable at that point?

just the item/record.  I'm doing arrival rate calculations.  each record 
contains a set of arrival times and I am rewriting the record every time 
a new entry arrives.  complete page or table locking will work in the 
sense that it will prevent collisions but it will have an increasing 
impact as load and simultaneous table but not record accesses increase.

---eric