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Re: vehicle to autoparts relationships

From: Aloha Kakuikanu <aloha.kakuikanu_at_yahoo.com>
Date: 22 Nov 2006 17:50:19 -0800
Message-ID: <1164246619.561011.4440@k70g2000cwa.googlegroups.com>

NENASHI, Tegiri wrote:
> "Aloha Kakuikanu" <aloha.kakuikanu_at_yahoo.com> wrote in
> news:1164244417.310045.85570_at_e3g2000cwe.googlegroups.com:
> > NENASHI, Tegiri wrote:
> >> You want to say the set containment join, is not it ? If you do,
> >> there are two problems: 1) the performance of set containment join;
> >> 2) the set valued attribute, or relation valued attribute, is not
> >> realised by all the databases. One can have a separate relation in
> >> the place of the relation valued attribute, of course, but then how
> >> does one reference the relation from AssemblyParts with
> >> assemblyPartNo ?
> >
> > No nested relations.
>
> Then how you create the schema ? Please show with tables: what is it
> that assemblyPartNo references ?

(referred to the rifle diagramm example above)

table Parts:
part# partName

------  -------------
100 - BARREL
102 - BARREL NUT
104 - BARREL EXTENSION
108 - BARREL RETAINER
110 - BOLT
112 - EXTRACTOR
114 - EXTRACTOR AXIS
116 - EJECTOR

...
194 - EXTRACTOR SPRING
...

table AssemblyParts:
assemblyPart# part# partName

-----------------  ----- -------------
1               112    EXTRACTOR ASSEMBLY
1               114    EXTRACTOR ASSEMBLY
1               194    EXTRACTOR ASSEMBLY
1               112    BOLT ASSEMBLY
1               114    BOLT ASSEMBLY
1               194    BOLT ASSEMBLY
1               110    BOLT ASSEMBLY
1               116    BOLT ASSEMBLY

In this particular example we see that

{112,114,194} <= {112,114,194,110,116}

in other words, BOLT ASSEMBLY includes EXTRACTOR ASSEMBLY. Received on Wed Nov 22 2006 - 19:50:19 CST

Original text of this message

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