hello

how can I make this restrictions:
1. if I need to recieve a string/integer, I want to make sure that I want get an empty string or empty integer
2. what do I need to do in order to recieve on 2 letters/digits and the letters must be upper case. (can recieve either digits/letters.
3. how can I make a string/integer with max number of letter/digits (not fix, since I dont know how many symbols I will enter)

thanks
Kfir

I assume you're asking about how to impose these constraints using XML Schema?

1. (I assume by "I want get" you mean "I won't get"). There's no such thing as an empty integer so you don't need to prevent it. You can prevent an empty string using <xs:minLength value="1"/>

2. <xs:pattern value="[A-Z0-9][A-Z0-9]"/>

3. for string: maxLength. For integer, specify maxInclusive value="999999" say.

These are very basic questions, I'm surprised you found it difficult to find the answers. Don't try using XML Schema without a reference book on your desk - even experienced users find it hard to remember the syntax.

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

for 1.
is it correct to write it like that?
<xs:attribute name="internal_name" type="xs:string" use="required" >
    <xs:minLength value="1"/>
</xs:attribute>

No, you need to declare an <xs:simpleType> and an <xs:restriction>

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

when I am trying to write
<xs:attribute name="internal_name" type="xs:string" use="required" >
    <xs:simpleType>
        <xs:minLength value="1"/>
    </xs:simpleType>
</xs:attribute>

it says that it is unexpected in simpleType expected xs:annotation, restriction, list or union.
when I write the same thing with out the simpleType it still that there is an error that it is expected to be simpleType .

sorry for all the Q but it is the first time I am working with this tool.
thank you very much for your help
kfir

You need an xs:restriction element inside the xs:simpleType

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

do you have a good reference book to recommand that I can find on the net?

thank you

We're on a Wrox site, so I'm a bit reluctant to recommend the competition: but I must admit that of the three XML Schema books on my bookshelf, the one I turn to first is Eric van der Vlist (O'Reilly).

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

thanks