Are SFDC IDs unique across all of SFDC or can you only assume an ID is unique within a particular org? If an sObject with a particular ID is deleted, could that ID come back again in the same org or another one for a new sObject?

Attribution to: Ryan Elkins

Possible Suggestion/Solution #1

For your initial question:

Reference

http://boards.developerforce.com/t5/General-Development/are-user-ids-unique-across-all-salesforce-com-prod-orgs/td-p/234975

Short Answer

Yes for Production Orgs (Sandbox's can have the same object Id as the Production Org they were cloned from)

For your second question:

I would expect this to be the case however I wouldn't rely on it as with any auto increment field in a database there could come a day when those Id's are reallocated for use.

Attribution to: Jon Hazan
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