sql - Trying to get a third normal form -
i edited question make more understandable:
i got tiny problem , don't know how handle it.
lets got table following attributes , values want transform third nf. table created automatically machine:
keyid | action | class | method | storenr. | country 1 | action1 | class1 | method1 | 123 | gb 1 | action2 | class2 | method2 | 123 | gb 2 | action5 | class5 | method5 | 335 | null 2 | action8 | class8 | method8 | 335 | null 3 | action2 | class2 | method2 | null| nl 3 | action5 | class5 | method5 | null| nl 4 | action4 | class4 | method4 | null| null 4 | action1 | class1 | method1 | null| null
as can see attributes keyid, action, class , method cant null. storenr , country can null.
the dependencies following:
method -> action action -> class storenr -> country
my problem keyid. randomly created number serves purpose of tracking useractions. wouldnt there keyid impossible kind of actions user4 used in session.
i dont know how handle when putting table third nf.
i hope made needs more clear :)
regards thomas
your stated set of dependencies
method -> action action -> class storenr -> country
and sample data suggests @ least 6 relations, follows. depending on intended nulls in sample data may simpler making it. nulls not need part of stated business requirement or fd - merely technical feature of implementation have created.
r1 {method,action} key {method} r2 {action,class} key {action} r3 {storenr,country} key {storenr} r4 {method,keyid} key {method,keyid} r5 {method,keyid,country} key {method,keyid} r6 {method,keyid,storenr} key {method,keyid}
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