XSD: Check in sets of attributes, that values aren't duplicates
Is it possible to check duplicate attribute values within same element using an XSD ?
For example:
In the above example, a pencil and an eraser belong to same category and have same code. How can I control that no product ("MyProduct") can have same category *and* code?
(if possible)
Note: in above example, categories and codes have a specific list of values (i.e. I know I have 12 categories and 728 codes).
Thank you
For example:
<MyProduct category="school" code="123">Pencil</MyProduct>
<MyProduct category="home" code="343">Vase</MyProduct>
<MyProduct category="home" code="752">Fork</MyProduct>
<MyProduct category="school" code="123">Eraser</MyProduct>In the above example, a pencil and an eraser belong to same category and have same code. How can I control that no product ("MyProduct") can have same category *and* code?
(if possible)
Note: in above example, categories and codes have a specific list of values (i.e. I know I have 12 categories and 728 codes).
Thank you
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ASKER
Checking your solution, much appreciated.
My XML begins like this:
May I assume that the "report" is the root element ?
My XML begins like this:
<?xml version="1.0" encoding="ISO-8859-1"?>
<report xmlns="http://www.w3.org/2001/XMLSchema-instance">
<control>....</control>
<data>...</data>
<audit>...</audit>
</report>May I assume that the "report" is the root element ?
report is the root. But if all MyProduct are grouped in a single container node, it is good for performance not to require uniqueness over the entire document, but just on the container node... it is wise to choose the context well
ASKER
My container node is the <data> node. However, the XML might have multiple (identical as per the structure) data nodes. I.e.
and inside <data> I have <MyProduct> elements among other things. Should I use the <data> ?
<?xml version="1.0" encoding="ISO-8859-1"?>
<report xmlns="http://www.w3.org/2001/XMLSchema-instance">
<control>....</control>
<data>...</data>
<data>...</data>
<data>...</data>
...
<audit>...</audit>
</report>and inside <data> I have <MyProduct> elements among other things. Should I use the <data> ?
If MyProduct needs to be unique within a single data node, use data for the xs:unique if you need uniqueness on a bigger scope, choose a bigger scope. It is the requirement that drives the scope. That should be your call, not mine
ASKER
Very accurate and fully working. Thank you very much for the extra advices.
Welcome
So I have assumed a parent MyRoot
In that context you set the xs:unique
nice thing about xs:unique is that you can set two xs:field, so you can mandate the uniqueness of a set rather than a single value