Record locking

[Jay R. Ashworth]

On Wed, Mar 31, 2004 at 10:28:24AM -0600, Mike Schwartz-PC Support & Services wrote:
> 	However I only have to check for duplicates if they have hand
> entered any number, or attempted to change the number I automatically
> assigned.  There isn't any need to check my automatically generated numbers,
> because I know there couldn't possibly be any duplicates.

Any sentence that contains the words "because there couldn't possibly
be" means your system specification isn't tight enough.  :-)

What happens if someone manually resets the "Next Document Number" in
the control file?  How about if an index gets bent?  There are half a
dozen ways that a number could end up duplicated; if unique numbers are
important to you (and your DBMS engine isn't enforcing them ;-), then
check.

Cheers,
-- jra
-- 
Jay R. Ashworth                                                jra at baylink.com
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        "They had engineers in my day, too."  -- Perry Vance Nelson