Including / importing local schemas that have namespaces - xsd

Question

Here is a schema file, midi.xsd that defines a type, note, used to store MIDI note values:
<?xml version="1.0" encoding="utf-8"?>
<xs:schema elementFormDefault="qualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:simpleType name="note">
<xs:restriction base="xs:integer">
<xs:minInclusive value="0"/>
<xs:maxInclusive value="127"/>
</xs:restriction>
</xs:simpleType>
</xs:schema>
Here is another schema file, octaves.xsd which uses midi.xsd to help define the layout to be enforced on an XML file containing data about octaves:
<?xml version="1.0" encoding="utf-8"?>
<xs:schema elementFormDefault="qualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:include schemaLocation="midi.xsd"/>
<xs:element name="octaves">
<xs:complexType>
<xs:sequence>
<xs:element name="octave">
<xs:complexType>
<xs:sequence>
<xs:element name="name" type="xs:string" />
<xs:element name="midi">
<xs:complexType>
<xs:sequence>
<xs:element name="value" type="xs:integer" />
<xs:element name="from" type="note" />
<xs:element name="to" type="note" />
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
<xs:attribute name="index" type="xs:integer" />
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
This is fine, and works exactly as you would expect it to, except that I have another requirement: I want note to be in its own namespace, midi, so that
<xs:element name="from" type="note" />
becomes
<xs:element name="from" type="midi:note" />
Try as I might, I cannot get this to work. My attempts have included use of the targetNamespace attribute in various places, the import element, and liberal use of xmlns:midi="...", but to no avail. I'd post one of these attempts here, were it not so cringe-worthy.
Could some kind soul point me in the right direction? I'm pretty sure the problem is to do with the fact that midi.xsd is a local file; it has never been, and never will be, hosted on a web server.

Answer 1

Change midi.xsd to be:
<xs:schema elementFormDefault="qualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
targetnamespace="/my/midi/namespace">
And then change octaves.xsd to say:
<xs:schema elementFormDefault="qualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:midi="/my/midi/namespace">
<xs:import namespace="/my/midi/namespace" schemaLocation="midi.xsd"/>
...
<xs:element name="from" type="midi:note" />
Note the use of xs:import rather than <xs:include> The two are very different - you use import for bringing in other namespaces, and include for inline inclusion of other schema files into the current namespace.
Note also that /my/midi/namespace can be anything you want, it's an arbitrary identifier.
I'm pretty sure the problem is to do with the fact that midi.xsd is a local file
Nope, not relevant.