Razzak, You also forgot to mention that the GUID is used by RBASE as part of the .$$$ file names used by RBASE.
Jim Bentley, American Celiac Society 1-504-737-3293 ________________________________ From: A. Razzak Memon <[email protected]> To: RBASE-L Mailing List <[email protected]> Sent: Thursday, October 18, 2012 12:06 PM Subject: [RBASE-L] - Re: DateTime tutorial At 09:36 AM 10/18/2012, Stephen Markson wrote: > Quick story illustrating why you should never use DATETIME for a unique > identifier: > We hired an experienced, reputable firm to create a web commerce app for us. > They > used a 12-digit order number. We asked them to reduce it to 9 digits so we > could use > (R:Base) integers in our application. At that time, I noticed that the order > number > was incrementing proportionally to the time, at a rate of 1 per 60 > microseconds. I > pointed out that decreasing the order # to 9 digits would increase the > probability > of a duplicate order # by a factor of 1,000. They said they'd get back to me. > A few > weeks later we got two orders with identical order numbers. To say the least, > I was > surprised that they had no primary key based on order #! Stephen, Very interesting story ... Did you know that R:BASE eXtreme 9.5 (64) include BIGNUM and GUID data types to handle such circumstances? In addition to so many cool features/enhancements, Globally Unique Identifier (GUID) data type in R:BASE eXtreme 9.5 (64) can also be used for a unique Row Identifier. For complete details ... http://www.rbase.com/rbg95 http://www.rbase.com/rbg95/compare.php Very Best R:egards, Razzak. www.rbase.com www.facebook.com/rbase
