DA Morgan wrote:
> Giraffe wrote:
>
>> Hi all,
>>
>> Please bear with me I've tried to make my question as terse as possible,
>> whilst not appearing confusing (hopefully I've not failed in this
>> regard).
>>
>> I'm trying to store a Chart configuration in an Oracle database
>> (although I'm hoping that my choice of database will not lead to a
>> solution specific to it, since so far my database is not platform, or
>> database specific).
>>
>> One of these chart entities has two or more axes (one x and at least one
>> y) related to it, and each axis relates to zero or more plot entities
>> (which store plot information such as plot type, line or columns/bars
>> etc). these plot entities relate to a specific item of data that can be
>> plotted (and relates to a Unit table).
>>
>> So far I have
>>
>> relations-> Chart (1-3) Axis (0-many) Plot (Many-1) DataItem
>>
>> (I'm assuming I've got this relationship right)
>>
>> How can I now insert a relationship with a Unit entity so that I can
>> ensure that Axis and Plot can refer to any unit in the unit relation *so
>> long as its the same Unit*. I'd like to enforce at a relational level a
>> limitation so that any number of plots can be configured for a specific
>> axis so long as they are all of the same unit. For instance income and
>> outgoings can both be related to an axis since they share the same unit
>> of currency. But weight and income cannot be plots that relate to one
>> axis since there are two units here and an axis can refer to only one
>> unit.
>>
>> It's easy to enforce this in my application but I was hoping to somehow
>> put in some kind of constraint at the database level to stop people
>> setting up charts with an axis that allows income, weight, and time to
>> all be plotted on the same axis.
>>
>> Perhaps someone has stored a chart configuration in a database before
>> and can offer me some insight.
>>
>> Many thanks,
>>
>> Giraffe.
>
>
> Trying to be platform neutral is a recipe for unscalable and lousy
> performance. Build 95% of the product to be neutral and then, as Oracle
> does, build a comptability layer that allows you to use best practices
> on the system.
>
> If you want charting don't reinvent the wheel. Look to what you've
> already purchase: Oracle Spatial.
>
> http://www.oracle.com/pls/db102/ranked?word=SDO
Ugh! Are you seriously recommending the network data model?
Received on Sat Aug 12 2006 - 12:15:27 CDT
