XML Schema for No-Location, User-defined Indexing Procedure

This section describes additional constraints imposed on the XML document returned by the user-defined lexer indexing procedure when the third parameter is FALSE. The XML document returned must be valid with respect to the following XML Schema:

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">

  <xsd:element name="tokens">
    <xsd:complexType>
      <xsd:sequence>
        <xsd:choice minOccurs="0" maxOccurs="unbounded">
          <xsd:element name="eos" type="EmptyTokenType"/>
          <xsd:element name="eop" type="EmptyTokenType"/>
          <xsd:element name="num" type="xsd:token"/>
          <xsd:group ref="IndexCompositeGroup"/>
        </xsd:choice>
      </xsd:sequence>
    </xsd:complexType>
  </xsd:element>

  <!--
  Enforce constraint that compMem element must be preceded by word element
  or compMem element for indexing
  -->
  <xsd:group name="IndexCompositeGroup">
    <xsd:sequence>
      <xsd:element name="word" type="xsd:token"/>
      <xsd:element name="compMem" type="xsd:token" minOccurs="0"
maxOccurs="unbounded"/>
    </xsd:sequence>
  </xsd:group>

  <!-- EmptyTokenType defines an empty element without attributes -->
  <xsd:complexType name="EmptyTokenType"/>

</xsd:schema>

Here are some of the constraints imposed by this XML Schema:

The root element is tokens. This is mandatory. It has no attributes.
The root element can have zero or more child elements. The child elements can be one of the following elements: eos, eop, num, word, and compMem. Each of these represent a specific type of token.
The compMem element must be preceded by a word element or a compMem element.
The eos and eop elements have no attributes and must be empty elements.
The num, word, and compMem elements have no attributes. Oracle Text will normalize the content of these elements as follows: convert whitespace characters to space characters, collapse adjacent space characters to a single space character, remove leading and trailing spaces, perform entity reference replacement, and truncate to 255 bytes.

Table 2-33 describes the element names defined in the preceding XML Schema.

Table 33 User-defined Lexer Indexing Procedure XML Schema Element Names

Element	Description
word	This element represents a simple word token. The content of the element is the word itself. Oracle Text does the work of identifying this token as being a stop word or non-stop word and processing it appropriately.
num	This element represents an arithmetic number token. The content of the element is the arithmetic number itself. Oracle Text treats this token as a stop word if the stoplist preference has `NUMBERS` added as the stopclass. Otherwise this token is treated the same way as the word token. Supporting this token type is optional. Without support for this token type, adding the `NUMERBS` stopclass will have no effect.
eos	This element represents end-of-sentence token. Oracle Text uses this information so that it can support `WITHIN` `SENTENCE` queries. Supporting this token type is optional. Without support for this token type, queries against the `SENTENCE` section will not work as expected.
eop	This element represents end-of-paragraph token. Oracle Text uses this information so that it can support `WITHIN` `PARAGRAPH` queries. Supporting this token type is optional. Without support for this token type, queries against the `PARAGRAPH` section will not work as expected.
compMem	Same as the word element, except that the implicit word offset is the same as the previous word token. Support for this token type is optional.

Examples

Document: Vom Nordhauptbahnhof und aus der Innenstadt zum Messegelände.

Tokens:

<tokens>
  <word> VOM </word>
  <word> NORDHAUPTBAHNHOF </word>
  <compMem>NORD</compMem>
  <compMem>HAUPT </compMem>
  <compMem>BAHNHOF </compMem>
  <compMem>HAUPTBAHNHOF </compMem>
  <word> UND </word>
  <word> AUS </word>
  <word> DER </word>
  <word> INNENSTADT </word>
  <word> ZUM </word>
  <word> MESSEGELÄNDE </word>
  <eos/>
</tokens>

Document: Oracle Database 11g Release 1

Tokens:

<tokens>
  <word> ORACLE11G</word>
  <word> RELEASE </word>
  <num> 1 </num>
</tokens>

Document: WHERE salary<25000.00 AND job = ‘F&B Manager’

Tokens:

<tokens>
  <word> WHERE </word>
  <word> salary<2500.00 </word>
  <word> AND </word>
  <word> job </word>
  <word> F&B </word>
  <word> Manager </word>
</tokens>