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Re^2: Tree Structure and Db

by simonm (Vicar)
on Jul 06, 2005 at 16:26 UTC ( #472867=note: print w/replies, xml ) Need Help??

in reply to Re: Tree Structure and Db
in thread Tree Structure and Db

In a tree-wise data structure, with only one parent per child, what is the perceived advantage of using this linking table rather than just adding the parent ID to the main table?

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Re^3: Tree Structure and Db
by SimonClinch (Deacon) on Jul 07, 2005 at 11:18 UTC
    A link table is the normal way to enforce referential integrity in many to many relationships (0 or 1 counts as many for these purposes) and in this case prevents orphans; it also enables you to define different types of relationship without putting more illegal or awkwardly-implemented constraints (and adding maybe-null foreign keys for them) on the master table.

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[karlgoethebier]: Discipulus: No. See https://en. wiki/Tribe_( Native_American)
[karlgoethebier]: They took Unix from some aliens
[marioroy]: Perl is so powerful that it can poll 40 metrics from 20 million devices in 40 minutes using 4 nodes only.
[karlgoethebier]: http://www. aliens.htm
[Lady_Aleena]: marioroy, I can't decide whether or not to move my RolePlaying:: Random:: modules to just Random::. I'm not as sophisticated as most here.
[marioroy]: Naming things can be difficult, sometimes more so that the actual code :)
[karlgoethebier]: Lady_Aleena: You need to jump to some conclusion
[Lady_Aleena]: And what would I rename RolePlaying/Random .pm to if I move all the RolePlaying/Random modules to just Random? Random/ Random/, maybe lowercase the file name to indicate it is a bit different? I don't know yet.
[marioroy]: What does Random do?
[karlgoethebier]: https://www. v=42WNHGr1jGI

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