Beispiel

- Application:
  - Person (0..n):
    - firstName (Zeichenfolge)
    - lastName (Zeichenfolge)
    - Income (0..n):
      - type (Code aus Codetabelle "IncomeType")
      - amount (Zahl)

- Application #1234:
  - Person #1235:
    - firstName: John
    - lastName: Smith
    - Income: <keine Datensätze>
  - Person #1236:
    - firstName: Mary
    - lastName: Smith
    - Income #1237:
      - type: Part-time
      - amount: 25
    - Income #1238:
      - type: Part-time
      - amount: 30

<?xml version="1.0" encoding="UTF-8"?>
<RuleSet name="DataStoreMappingExample"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:noNamespaceSchemaLocation=
"http://www.curamsoftware.com/CreoleRulesSchema.xsd">

  <!-- NB no rule class for the CDS entity type "Application";
       the attributes stored directly on an Application are 
       not required by rules, so no point creating a rule object
       which won't get used. -->

  <!-- The name of this rule class matches that of a CDS entity
       type -->
  <Class name="Person">
    <!-- The name of this rule attribute matches that of an
         attribute on the CDS entity type, and so its value will
         be automatically specified by the
         DataStoreRuleObjectRetriever. -->
    <Attribute name="firstName">
      <!-- The type of the rule attribute must agree with the
           type of the CDS attribute type, otherwise CER will
           issue a runtime error. -->
      <type>
        <javaclass name="String"/>
      </type>
      <derivation>
        <specified/>
      </derivation>
    </Attribute>

    <!-- NB no rule attribute for the CDS attribute for lastName.
 -->

    <!-- Rule attributes matching the "childEntities_<rule class
 name>"
         pattern will receive special treatment from the
         DataStoreRuleObjectRetriever.
    
         The DataStoreRuleObjectRetriever will specify the value of
         this attribute to be all the rule objects created from the
         child Income records which belong to this Person's record
         in the CDS. -->
    <Attribute name="childEntities_Income">
      <!-- The type must be a list of Income rule objects -->
      <type>
        <javaclass name="List">
          <ruleclass name="Income"/>
        </javaclass>
      </type>
      <derivation>
        <specified/>
      </derivation>
    </Attribute>
  </Class>

  <!-- The name of this rule class does not match any CDS entity
 type,
       so the DataStoreRuleObjectRetriever will not create any rule
       objects for this rule class. -->
  <Class name="Benefit">
    <Attribute name="amount">
      <type>
        <javaclass name="Number"/>
      </type>
      <derivation>
        <specified/>
      </derivation>
    </Attribute>
  </Class>

  <Class name="Income">
    <!-- A rule attribute named "parentEntity" will receive
        special treatment from the
        DataStoreRuleObjectRetriever.
      
        The DataStoreRuleObjectRetriever will specify the value
        of this attribute to be the rule object created from the
        Person record which is the parent of this Income record
        in the CDS. -->
    <Attribute name="parentEntity">
      <!-- The type must be a single Person rule object -->
      <type>
        <ruleclass name="Person"/>
      </type>
      <derivation>
        <specified/>
      </derivation>
    </Attribute>

    <Attribute name="type">
      <type>
        <!-- The type of this attribute must specify the correct 
             code table, matching the CDS domain definition. -->
        <codetableentry table="IncomeType"/>
      </type>
      <derivation>
        <specified/>
      </derivation>
    </Attribute>

    <Attribute name="amount">
      <type>
        <javaclass name="Number"/>
      </type>
      <derivation>
        <!-- This derivation will never be executed, as 
             the DataStoreRuleObjectRetriever will automatically
             "specify" the value from that on the CDS record; 
             once a value is specified CER does not attempt to
             calculate it.
        
             In general, attributes which expect to be populated
             by the DataStoreRuleObjectRetriever should be marked
             as <specified/> to avoid any confusion between
             stand-alone testing of your rule sets and testing
             with the DataStoreRuleObjectRetriever.
        -->
        <Number value="123"/>
      </derivation>
    </Attribute>

    <!-- This attribute is not present on the CDS entity type, 
         so will not be populated.  This is exactly what we 
         want, because its value is derived from other 
         rule attributes in the normal CER way. -->
    <Attribute name="isCountable">
      <type>
        <javaclass name="Boolean"/>
      </type>
      <derivation>
        <choose>
          <type>
            <javaclass name="Boolean"/>
          </type>
          <test>
            <reference attribute="type"/>
          </test>
          <when>
            <condition>
              <Code table="IncomeType">
                <String value="Full-time"/>
              </Code>
            </condition>
            <value>
              <true/>
            </value>
          </when>
          <when>
            <condition>
              <Code table="IncomeType">
                <String value="Part-time"/>
              </Code>
            </condition>
            <value>
              <true/>
            </value>
          </when>
          <otherwise>
            <value>
              <false/>
            </value>
          </otherwise>
        </choose>
      </derivation>
    </Attribute>

    <!-- This rule attribute is not calculated, nor
         does it correspond to an attribute on the
         CDS entity type.
    
         If the value of this attribute is referenced
         at runtime, CER will report a runtime error:
         "Value must be specified before it is used 
          (it cannot be calculated)."
    -->
    <Attribute name="employerName">
      <type>
        <javaclass name="String"/>
      </type>
      <derivation>
        <specified/>
      </derivation>
    </Attribute>
  </Class>

</RuleSet>