You can join on any two columns with similar datatypes.
There does not have to be an explicit Parent-Child (PK-FK) relationship.
However, without a relationship, the question is: would the data provide any
useful information? And the answer is: it depends.
If that helps, then I was lucky. If not, please ask again, offering some
information about what you are seeking.
Regards,
--
Arnie Rowland, YACE*
"To be successful, your heart must accompany your knowledge."
*Yet Another certification Exam
"Simon Harris" <too-much-spam@.makes-you-fat.com> wrote in message
news:%23t9mnTWlGHA.4268@.TK2MSFTNGP05.phx.gbl...
> Hi All,
> I'm currently studying for MCP exam 70-229. I'm on the database logical
> modeling section, and have come up with this question:
> In a non-identifying relationship, how would a join work, or is the
> term used to describe a situation where a relationship is at fault?
> Many Thanks,
> Simon.
>Hi Arnie,
Thanks for the post, I do understand that a relatioship can be either
explicit or implicit, but I'm not sure this is what the question refers to,
to bo honest, I'm not 100% sure what the question means myself!
Heres an excerpt from the book I'm working from:
"A relationship is said to be identifying if the primary key of a child
entity contains all the attributes of a foreign key. If the primary key of
the child entity does not contain all the attributes of a foreign key, the
the relationship is non-identifying"
The more I read that statement, the more confused I get! 8o)
Any ideas?
Simon.
"Arnie Rowland" <arnie@.1568.com> wrote in message
news:uTMqldWlGHA.884@.TK2MSFTNGP05.phx.gbl...
> Your question is not very clear.
> You can join on any two columns with similar datatypes.
> There does not have to be an explicit Parent-Child (PK-FK) relationship.
> However, without a relationship, the question is: would the data provide
> any useful information? And the answer is: it depends.
> If that helps, then I was lucky. If not, please ask again, offering some
> information about what you are seeking.
> Regards,
> --
> Arnie Rowland, YACE*
> "To be successful, your heart must accompany your knowledge."
> *Yet Another certification Exam
>
> "Simon Harris" <too-much-spam@.makes-you-fat.com> wrote in message
> news:%23t9mnTWlGHA.4268@.TK2MSFTNGP05.phx.gbl...
>|||Hi All,
I'm currently studying for MCP exam 70-229. I'm on the database logical
modeling section, and have come up with this question:
In a non-identifying relationship, how would a join work, or is the term
used to describe a situation where a relationship is at fault?
Many Thanks,
Simon.|||Your question is not very clear.
You can join on any two columns with similar datatypes.
There does not have to be an explicit Parent-Child (PK-FK) relationship.
However, without a relationship, the question is: would the data provide any
useful information? And the answer is: it depends.
If that helps, then I was lucky. If not, please ask again, offering some
information about what you are seeking.
Regards,
--
Arnie Rowland, YACE*
"To be successful, your heart must accompany your knowledge."
*Yet Another certification Exam
"Simon Harris" <too-much-spam@.makes-you-fat.com> wrote in message
news:%23t9mnTWlGHA.4268@.TK2MSFTNGP05.phx.gbl...
> Hi All,
> I'm currently studying for MCP exam 70-229. I'm on the database logical
> modeling section, and have come up with this question:
> In a non-identifying relationship, how would a join work, or is the
> term used to describe a situation where a relationship is at fault?
> Many Thanks,
> Simon.
>|||Hi Arnie,
Thanks for the post, I do understand that a relatioship can be either
explicit or implicit, but I'm not sure this is what the question refers to,
to bo honest, I'm not 100% sure what the question means myself!
Heres an excerpt from the book I'm working from:
"A relationship is said to be identifying if the primary key of a child
entity contains all the attributes of a foreign key. If the primary key of
the child entity does not contain all the attributes of a foreign key, the
the relationship is non-identifying"
The more I read that statement, the more confused I get! 8o)
Any ideas?
Simon.
"Arnie Rowland" <arnie@.1568.com> wrote in message
news:uTMqldWlGHA.884@.TK2MSFTNGP05.phx.gbl...
> Your question is not very clear.
> You can join on any two columns with similar datatypes.
> There does not have to be an explicit Parent-Child (PK-FK) relationship.
> However, without a relationship, the question is: would the data provide
> any useful information? And the answer is: it depends.
> If that helps, then I was lucky. If not, please ask again, offering some
> information about what you are seeking.
> Regards,
> --
> Arnie Rowland, YACE*
> "To be successful, your heart must accompany your knowledge."
> *Yet Another certification Exam
>
> "Simon Harris" <too-much-spam@.makes-you-fat.com> wrote in message
> news:%23t9mnTWlGHA.4268@.TK2MSFTNGP05.phx.gbl...
>
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