Question : XML data model

[laptop_01]

I am converting a legacy binary DB to XML. The DB is mostly used to store numeric arrays. Using array Temperature (x,y,z) as an example:

 

Temperature(1,1,1) = 99.4

Temperature(1,1,2) = 100.4

Temperature(1,1,3) = 200.4

...... and so forth

 

I am wondering what is the best way to model this? I am currently using this XML Tag plus XSLT to format the data:

 

<DS Name="NTCBDS" >

<Value D1="1" D2="1" D3="1"> 99.4 </Value>

<Value D1="1" D2="1" D3="2"> 100.2 </Value>

<Value D1="1" D2="1" D3="3"> 200.1 </Value>

<Value D1="1" D2="2" D3="1"> 190.3 </Value> ........ ans so forth

</DS>

 

Sometimes, I will need to query the data based on D1, or D2, or D3. For example, I may ask for all data values where D3=5 (ie, select all values where D3=5 (fixed), D1 goes from 1 to MAX and D2 goes from 1 to MAX).

 

Question:

Is the above model good or fit for such search using XSL. If yes, could you give a sample XSL to do the scenario I mentioned above. I don't seem to be able to get it right.

 

OR should I be using:

 

<DS Name="NTCBDS" >

<Value>

<D1>"1"</D1>

<D2>"1"</D2>

<D3>"1"</D3>

99.4 </Value>

<Value>

<D1>"1"</D1>

<D2>"1"</D2>

<D3>"2"</D3>

100.2 </Value>

<Value>

<D1>"1"</D1>

<D2>"1"</D2>

<D3>"3"</D3>

200.1 </Value>

</DS>

 

With the assumption that since D1,D2 and D3 are now elements, I may have more template power ... I am semi new to XSLT.

 

Thanks

[XyBoy]

I don't think it makes much of difference. Have a look at the XPath specs or at a tutorial. I haven't been writing XSL for some time, but as far as I can remember, you can use XPath expressions with the XML DOM, like this :

 

yourXMLDocument.SelectNodes (XPathExpression) -> it returns all the nodes that match the expression.

 

XPath allows you to select a node based on its attributes and/or on its parents/children nodes values.

 

For instance, your XPath expression would be something like :

1. for the first structure you described :

/DS/Value[@D1=x AND @D2=y]

(returns the nodes of type "Value" that have a parent of type "DS" that is at the root of the doc AND for which the D1 attribute equals x and the D2 attribute equals y; I'm not sure of the "AND" syntax, look at the specs).

 

2. for the second structure :

/DS/Value[D1=1 AND D2=2]

(the same, but D1 and D2 are children, not attributes). Note : I don't think you need the double-quotes in your XML file : <D3>3</D3> is ok.

 

Hope this helps. To adapt this to an XSLT file, it's not very difficult. I can show you an example if you want.

Bye.

Xyboy.