2014-09-23 19:19 GMT+02:00 Carlos Catucci <carlos.catu...@gmail.com>:
> > 2014-09-23 17:32 GMT+02:00 Marco Fochesato <marco...@gmail.com>: > > > > Va bene! > > Si infatti, per "sentirmi stretto", parlavo di quello: perchè deve > esserci per forza na colonna id?? > > 1 - It's faster. A JOIN on an integer is much quicker than a JOIN on a > string field or combination of fields. It's more efficient to compare > integers than strings. > > 2 - It's simpler. It's much easier to map relations based on a single > numeric field than on a combination of other fields of varying data types. > > 3 - It's data-independent. If you match on the ID you don't need to worry > about the relation changing. If you match on a name, what do you do if > their name changes (i.e. marriage)? If you match on an address, what if > someone moves? > > 4 - It's more efficient If you cluster on an (auto incrementing) int > field, you reduce fragmentation and reduce overall size of the data set. > This also simplifies indexes needed to cover your relations. > Certo certo certo! Non discuto il fatto che un integer stia bene come id. Mi lamentavo solo del NOMEella colonna: perchè si deve per forza chiamare ID, con Django? Al problema mi ha già risolto Daniele. > > > Fai pure > > > Grazie! -- Marco Fochesato
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