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Hi James,

Yes, and correctly done application-wide, you theoretically shouldn't need to pre-check for existence or worry about duplicates when writing.  And since this about design, presumably of a new application, that makes sense.

Tim Father's suggestion of CMPSWP is interesting -- I'd never heard of that. Sounds like a good basis for an identifier factory.

--
*Peter Dow* /
Dow Software Services, Inc.
909 793-9050
petercdow@xxxxxxxxx <mailto:petercdow@xxxxxxxxx>
pdow@xxxxxxxxxxxxxx <mailto:pdow@xxxxxxxxxxxxxx>

/
On 12/14/2020 1:14 PM, James H. H. Lampert wrote:
On 12/14/20 10:37 AM, Peter Dow wrote:
Pre-checking for existence doesn't always work. If you have a bunch of jobs adding to the file at the same time, there's a pretty good chance that between the time you pre-check and when you write the record, that some other job may beat you to the write.

So have your identifier factory set up in such a way that calling it puts an exclusive lock on something, that the calling program then has to explicitly release once the new record has been written.

--
JHHL


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