Re: UUID column as pimrary key?

On Jan 6, 2011, at 9:31 AM, Chris Browne wrote:

> The reasonable choices for a would-be artificial primary key seem to be
> 1 and 3; in a distributed system, I'd expect to prefer 1, as the time +
> host data are likely to eliminate the "oh, it might just randomly match"
> problem.

In some contexts, 1 is considered a security weakness, as it reveals information about which machine generated it and when, which is why most OS-supplied uuid generators now default to 4 (random). This tends to be more of a concern with encryption/security uses, and if it's not a concern for your db[*], then your are correct that 1 is likely the best choice.

[*] After all, in many dbs we log all sorts of explicit where/who/when for auditing purposes. In that case, having ids that provide a clue of where/when most certainly does not add any legitimate security concern.

-- 
Scott Ribe
scott_ribe@elevated-dev.com
http://www.elevated-dev.com/
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