This section contains information about the following:
As in TSD3, a collection name
is a value of type
xs:NMTOKEN. The name of a collection
identifies it uniquely within the entire database.
In TSD4, a doctype name is a QName, with the restriction that both the lexical and the expanded QName must be unique within the collection. The uniqueness of the lexical QName within the collection, effectively being just a plain string, is important especially for plain URL addressing (see X-Machine Programming).
Each doctype in a Tamino database has a namespace context. From a logical point of view, the namespace context is a table describing a unique mapping of prefixes to URIs. It is extracted from the doctype's schema document(s) from the following locations:
namespace declarations in the corresponding tsd:doctype
element (used for that doctype only);
namespace declarations in the xs:schema root element of
the schema document containing the tsd:doctype element (used for all doctypes
defined in that schema document);
namespace declarations in the tsd:collection document,
for the collection in which the doctype is contained. This document allows you
to assign properties to a collection, e.g. the namespace context or whether the
schemaless storage of documents is permitted in that collection. It can be
stored in Tamino using the
_DEFINE command. Please see below for an example.
The namespace declarations in this document affect all doctypes in the
collection.
Any prefix defined at one of these locations goes into the namespace
context. The order in which the places are listed reflects their priority; for
example, a namespace declaration given in the tsd:doctype element
overrides a namespace declaration given in the xs:schema root
element. For collections allowing for schemaless storage of documents, there
may not be a schema document. Hence, only the third location applies.
Note:
As the namespace context is crucial especially for the behavior of
existing applications developed with previous versions of
Tamino, namespace declarations contributing to the
namespace context of any doctype may not be modified or removed when updating a
schema.
Consider the following schema:
<xs:schema
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:tsd="http://namespaces.softwareag.com/tamino/TaminoSchemaDefinition"
xmlns:p1="URI1"
xmlns:p2="URI2"
targetNamespace="URI1" >
<xs:annotation>
<xs:appinfo>
<tsd:schemaInfo name="mySchema">
<tsd:collection name="myCollection"/>
<tsd:doctype name="p1:root"/>
<tsd:doctype name="p1:other" xmlns:p2="URI2a" xmlns:p3="URI3" xmlns:p5="URI5"/>
</tsd:schemaInfo>
</xs:appinfo>
</xs:annotation>
...
</xs:schema
with the following collection object:
<tsd:collection name="myCollection"
xmlns:tsd="http://namespaces.softwareag.com/tamino/TaminoSchemaDefinition"
xmlns:p2="URI2b"
xmlns:p3="URI3a"
xmlns:p4="URI4"
/>
The namespace context for the doctype with the lexical QName
p1:root is:
| Prefix | URI |
|---|---|
| p1 | URI1 |
| p2 | URI2 |
| p3 | URI3a |
| p4 | URI4 |
For doctype p1:other, the namespace context is:
| Prefix | URI |
|---|---|
| p1 | URI1 |
| p2 | URI2a |
| p3 | URI3 |
| p4 | URI4 |
| p5 | URI5 |
The namespace context of a doctype is used for different purposes:
Provide mapping of prefixes to URIs for X-Query
requests (see the _XQL and
_DELETE commands).
Lexical QNames within _XQL and
_DELETE requests are translated to expanded QNames before further
processing. This translation is based on the namespace context of the
corresponding doctype. If a query, e.g.
_XQL=/*/p:name
does not uniquely identify the doctype, it is first transformed to a representation where each expression refers to a unique doctype within the current collection.
Assuming the collection contains doctypes dt1,
dt2 and dt3, the query above can be transformed
to:
_XQL= /dt1/p:name | /dt2/p:name | /dt3/p:name
Then, the prefix p: can be mapped to a
URI for each of the doctypes dt1,
dt2, and dt3, based on the corresponding namespace
context. Note that the URI to which p: is mapped may differ
between the doctypes. If a prefix in the request cannot be mapped based on the
namespace context, it is assumed that there is no matching
QName in the documents. If a lexical QName does not have a
prefix, it is assumed that it does not belong to any namespace at
all.
A special case occurs when a doctype with the schema's
targetNamespace attribute is associated with the
default namespace in the respective schema document. Consider the following
schema:
<xs:schema
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:tsd="http://namespaces.softwareag.com/tamino/TaminoSchemaDefinition"
xmlns="URI"
targetNamespace="URI" >
<xs:annotation>
<xs:appinfo>
<tsd:schemaInfo name="mySchema">
<tsd:collection name="myCollection"/>
<tsd:doctype name="root"/>
</tsd:schemaInfo>
</xs:appinfo>
</xs:annotation>
...
</xs:schema
The lexical QName of the doctype defined in the schema is just
root without any prefix. Its expanded QName is
(URI,root). In order to distinguish the doctype's lexical QName
from lexical QNames corresponding to expanded QNames not belonging to any
namespace, a prefix mapped to "URI" may be introduced via the
tsd:collection document. For example:
<tsd:collection name="myCollection"
xmlns:tsd="http://namespaces.softwareag.com/tamino/TaminoSchemaDefinition"
xmlns:p="URI" />
maps the prefix "p:" to "URI". After this
document has been stored in Tamino via
_DEFINE, a query _XQL=p:root can be
used to query all instances.
Plain URL addressing is based on a doctype's lexical QName, which is
required to be unique within the scope of a collection. Instances within the
doctype are identified either by their ino:id (a unique number) or
by their document name. Neither method depends on namespaces.
XQuery requests sent to Tamino (using the
_XQUERY command) are based on the W3C's XQuery
draft. They must specify a URI for each prefix used in the request. Hence, the
namespace context of a doctype is not needed.
The ino: namespace prefix can be used in various contexts.
If no namespace declaration is in scope, the following is assumed:
xmlns:ino="http://namespaces.softwareag.com/tamino/response2"
The ino: prefix may not be bound to any other URI.
Note:
This is not correct for XQuery.
When executing a _PROCESS command,
Tamino checks for the presence of an
ino:id attribute in the root element. If present, the request is
interpreted as an attempt to replace the original document identified by that
ino:id (if any; otherwise an error occurs). Any prefix other than
ino: does not lead to interpretation as a request for replacement
of the document — even when mapped to the same URI — and the document is
rejected.
_XQL queries and
_DELETE requests may use the ino:
prefix for the pseudo-attributes ino:id and
ino:docname without the need for the ino: prefix to
be mapped via the doctype's namespace context.
Instances of doctype ino:acl in collection
ino:security are used to configure access to specific collections,
doctypes and nodes within doctypes based on simple path expressions given
inside the ino:ace element(s). A valid entry for the previous
music schema might be:
<ino:acl
xmlns:ino="http://namespaces.softwareag.com/tamino/response2"
ino:ac lname="myAcl">
<ino:ace
xmlns:e = "http://www.softwareag.com/tamino/doc/examples/models/jazz/encyclopedia"
xmlns:i = "http://www.softwareag.com/tamino/doc/examples/models/instruments"
ino:access="change">/e:jazzMusician/e:plays/i:saxophone</ino:ace>
</ino:acl>