The featest pattern match

Question

Now I met a difficult question.Firstly,we have a criterion table as below:Combination Name     Service     UnitLength     UnitHeight     LoadStatus     Bill No ......(until unbounded fields). Some data like this
Combination Name |     Service |     UnitLength | UnitHeight | LoadStatus |     Bill No ......
COM1 | CSC | 40 | 96 |
COM2 | CSC | 40 | 96 | F |
COM3 | CSC | 40 | 96 | F | SEA-SCS
If there is an object has the attribute UnitLength equal 40 and UnitHeight equal 96 the correct combination COM1 is selected;otherwise, if
it has the attribute UnitLength equal 40  and UnitHeight equal 96 and LoadStatus equal F then the appropriate combination COM2 is selected; then if the object has UnitLength equal 40  and UnitHeight equal 96 and LoadStatus equal F  and many other conditions ,the featest  pattern match will be the completely match combination.But when there is no completely match combination,we may get a combination  closer match the object.For example,an object has the following attributes UnitLength equal 40 and UnitHeight equal 96 and LoadStatus equal F Bill No equal SEA-SCS* ,the best result will be COM3.
How can we find a pl/sql procedure resolve this question?
Thanks very much! Look forward to your answer!
About the combination structure(Combinaton.xsd) as below:
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xdb="http://xmlns.oracle.com/xdb" version="1.0" xdb:storeVarrayAsTable="true">
     <xs:element name="()" type="CombinationType" xdb:defaultTable="COMBINATION"/>
     <xs:complexType name="CombinationType" xdb:SQLType="Combination_T">
          <xs:sequence>
               <xs:element name="FilterNam" type="FilterNamType" xdb:SQLName="FilterNam"/>
               <xs:element name="Priority" type="PriorityType" xdb:SQLName="Priority"/>
               <xs:element name="FilterType" type="FilterType" minOccurs="0" xdb:SQLName="TYPE"/>
               <xs:element name="Service" type="ServiceType" xdb:SQLName="Service"/>
               <xs:element name="Operator" type="OperatorType" xdb:SQLName="Operator"/>
               <xs:element name="OperTim" type="OperTimType" xdb:SQLName="OperTim"/>
               <xs:element name="FilterItems" type="FilterItemsType" xdb:SQLName="FilterItems"/>
               <xs:element name="PlanMatrix" type="PlanMatrixType" xdb:SQLName="PlanMatrix"/>
               <xs:element name="Discription" type="DiscriptionType" xdb:SQLName="Discription"/>
          </xs:sequence>
     </xs:complexType>
     <xs:complexType name="FilterItemsType" xdb:SQLType="FilterItems_T">
          <xs:sequence>
               <xs:element name="FilterItem" type="FilterItemType" maxOccurs="unbounded" xdb:SQLName="FilterItem" xdb:SQLCollType="FilterItem_V"/>
          </xs:sequence>
     </xs:complexType>
     <xs:complexType name="FilterItemType" xdb:SQLType="FilterItem_T">
          <xs:sequence>
               <xs:element name="Charateristic" type="CharateristicType" xdb:SQLName="Charateristic"/>
               <xs:element name="Oper" type="OperType" xdb:SQLName="Oper"/>
               <xs:element name="Value" type="ValueType" xdb:SQLName="Value"/>
          </xs:sequence>
     </xs:complexType>
     <xs:complexType name="PlanMatrixType" xdb:SQLType="PlanMatrix_T">
          <xs:sequence>
               <xs:element name="PlanMatrixElement" type="PlanMatrixElementType" maxOccurs="3" xdb:SQLName="PlanMatrixElement" xdb:SQLCollType="PlanMatrixElement_V"/>
          </xs:sequence>
     </xs:complexType>
     <xs:complexType name="PlanMatrixElementType" xdb:SQLType="PlanMatrixElementTypem_T">
          <xs:sequence>
               <xs:element name="Interval" type="IntervalType" xdb:SQLName="Interval"/>
               <xs:element name="DaysBfETD" type="DaysBfETDType" xdb:SQLName="DaysBfETD"/>
               <xs:element name="Resevevation" type="ResevevationType" xdb:SQLName="Resevevation"/>
               <xs:element name="Algorithm" type="AlgorithmType" xdb:SQLName="Algorithm"/>
               <xs:element name="HDP" type="HDPType" xdb:SQLName="HDP"/>
          </xs:sequence>
     </xs:complexType>
     <xs:simpleType name="FilterNamType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="30"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="OperatorType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="10"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="ServiceType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="20"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="FilterType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="4"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="PriorityType">
          <xs:restriction base="xs:integer"/>
     </xs:simpleType>
     <xs:simpleType name="OperTimType">
          <xs:restriction base="xs:date"/>
     </xs:simpleType>
     <xs:simpleType name="CharateristicType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="35"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="OperType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="10"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="ValueType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="35"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="DiscriptionType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="35"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="IntervalType">
          <xs:restriction base="xs:integer"/>
     </xs:simpleType>
     <xs:simpleType name="DaysBfETDType">
          <xs:restriction base="xs:integer"/>
     </xs:simpleType>
     <xs:simpleType name="ResevevationType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="35"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="AlgorithmType">
          <xs:restriction base="xs:string">
               <xs:minLength value="1"/>
               <xs:maxLength value="35"/>
          </xs:restriction>
     </xs:simpleType>
     <xs:simpleType name="HDPType">
          <xs:restriction base="xs:string">
               <xs:minLength value="0"/>
               <xs:maxLength value="35"/>
          </xs:restriction>
     </xs:simpleType>
</xs:schema>
And the data(Combination.xml) like that:
<Combination
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="http://localhost/xml_test//Combination.xsd">
<FilterNam>40/8.6/F/BILL</FilterNam>
<Priority>5</Priority>
<Service>KR-SHIPPING-LINE</Service>
<Operator>ZHANGRUI</Operator>
<OperTim>2010-06-09</OperTim>
<FilterItems>
<FilterItem>
<Charateristic>UnitLegth</Charateristic>
<Oper>=</Oper>
<Value>40</Value>
</FilterItem>
<FilterItem>
<Charateristic>UnitHeigh</Charateristic>
<Oper>=</Oper>
<Value>8.6</Value>
</FilterItem>
<FilterItem>
<Charateristic>LoadStatus</Charateristic>
<Oper>=</Oper>
<Value>F</Value>
</FilterItem>
<FilterItem>
<Charateristic>BillNo</Charateristic>
<Oper>=</Oper>
<Value>SEA-BILLING-NO.1</Value>
</FilterItem>
</FilterItems>
<PlanMatrix>
<PlanMatrixElement>
<Interval>1</Interval>
<DaysBfETD>3</DaysBfETD>
<Resevevation>1 BAY</Resevevation>
<Algorithm>MIX VESSEL</Algorithm>
</PlanMatrixElement>
</PlanMatrix>
</Combination>
Edited by: user10904897 on 2010-6-9 下午8:23
Edited by: user10904897 on 2010-6-9 下午8:57

Answer 1

my best would be to do something like the following since i don't have oracle and can't simulate it right now:
select a.*,
       case when unitlength = 40 and unitheight = 96 and loadstatus ='F' and billno = 'SEA-SCS' then 'COM3'
              when unitlength = 40 and unitheight = 96 and loadstatus ='F' and billno != 'SEA-SCS' then 'COM2'
              when unitlength = 40 and unitheight = 96 and loadstatus != 'F' then 'COM1'
              else 'print what ever you want'
       end
from <table_name>
where <any_conditions_you_want_if_any>
;