-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 11/16/07 20:50, Greg Smith wrote: [snip] > > He doesn't use that example anymore but still misses the point I tried > to make. The ability of the world to invalidate the assumptions that go > into natural key assignment are really impressive. I particularly enjoy > that so many systems are built presuming that the Social Security number > for a person is involatile that this topic comes up in their FAQ about > identify theft: http://www.socialsecurity.gov/pubs/10064.html Natural PKs are *not* set in stone, and only stubborn fools won't admit that they can't divine all situations. So, you add a new column to the PK and keep on going. But still, there *are* some circumstances where natural PKs just don't work. After all, SSNs and credit card numbers are synthetic (just not generated sequential by the RDBMS). - -- Ron Johnson, Jr. Jefferson LA USA %SYSTEM-F-FISH, my hovercraft is full of eels -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFHPnLPS9HxQb37XmcRAggNAKCL8UDTQ3238mbYIiV32AUAnOs+aQCgkhTP yr+t6pT5loh7PBUc3QPljD4= =O/Eb -----END PGP SIGNATURE----- ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
