Hello.<div><br></div><div>I was looking at the schema that Koha uses for its database, and noticed a few peculiarities that I wonder if anyone could shed some light on:</div><div><br></div><div>The serial table uses VARCHAR(100) for serial.biblionumber and serial.subscriptionid. Is there any context in which those are not numeric identifiers? Presumably as a result of that, there are no foreign key constraints on the serial table. I think there probably should be.</div>
<div><br></div><div>There&#39;s a similar situation with the subscription table: subscription.biblionumber doesn&#39;t have a foreign key relation with biblio.biblionumber, nor, indeed, any index at all. Foreign keys are also lacking for subscription.aqbooksellerid and subscription.aqbudgetid.</div>
<div><br></div><div>On the subject of foreign keys, should items.itype have a foreign key linking it to itemtypes?</div><div><br></div><div>My understanding of foreign key relationships is that they&#39;re a Good Thing because they provide a means to ensure referential integrity. Am I missing something in these particular cases (and there are probably others, these are just the ones I happened to notice), or would people say this was probably just an oversight?</div>
<div><br></div><div>Regards,</div><div>Jared Camins-Esakov<br clear="all"><div><br></div>-- <br>Jared Camins-Esakov<div>Bibliographer, C &amp; P Bibliography Services, LLC</div><div>(phone) +1 (917) 727-3445</div><div>(e-mail) <a href="mailto:jcamins@cpbibliography.com" target="_blank">jcamins@cpbibliography.com</a></div>
<div>(web) <a href="http://www.cpbibliography.com/" target="_blank">http://www.cpbibliography.com/</a></div><br>
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