Removing duplicate records from xml - xslt

Question

<?xml version="1.0" encoding="utf-8"?>
<Employee_Data>
<Employee>
<NEW_HIRE_OR_REHIRE />
<RETIREMENT_BENEFITS />
<ADDRESS />
<PERSONAL>
<Record>
<SSN>327408678</SSN>
<WDEmpID>10032417</WDEmpID>
<Initiator />
<Effective>20141014</Effective>
<SeqNum>320</SeqNum>
<Last_Name>VAN TREECK</Last_Name>
<First_Name>DENISE</First_Name>
<Middle_Name>J</Middle_Name>
<Social_Suffix />
<Birth_Date>19560422</Birth_Date>
<Gender>F</Gender>
<Ethnicity>0</Ethnicity>
<Marital_Status_Date>19781202</Marital_Status_Date>
<Marital_Status>M</Marital_Status>
<CITIZENSHIP />
<Military_Service_Status />
<Disability />
<Indicator>PersonalRecordChangesIndicator</Indicator>
</Record>
</PERSONAL>
<STATUS />
<POSITION>
<Record>
<SSN>327408678</SSN>
<WDEmpID>10032417</WDEmpID>
<Initiator />
<Effective>20141006</Effective>
<SeqNum>250</SeqNum>
<ActionCode />
<DEFAULTJOBCODE>YYY01</DEFAULTJOBCODE>
<SAPJOBCODE>30000715</SAPJOBCODE>
<PayEntity>NC1</PayEntity>
<DIVISION>CORP</DIVISION>
<ORGANIZATION>GES</ORGANIZATION>
<COMPANYNUMBER>01</COMPANYNUMBER>
<LEDGERDEPARTMENT>CHEN050D</LEDGERDEPARTMENT>
<SALARY_GRADE>LC008</SALARY_GRADE>
<TEMPORARY_POSITION_INDICATOR_FOR_POSITION_RECORD />
<LocationCode>AP10</LocationCode>
<LocationDepartment>050D</LocationDepartment>
<WDEmpID>10032417</WDEmpID>
<Indicator>Position and Location Change Indicator</Indicator>
</Record>
<Record>
<SSN>327408678</SSN>
<WDEmpID>10032417</WDEmpID>
<Initiator />
<Effective>20141006</Effective>
<SeqNum>250</SeqNum>
<ActionCode />
<DEFAULTJOBCODE>YYY01</DEFAULTJOBCODE>
<SAPJOBCODE>30000715</SAPJOBCODE>
<PayEntity>NC1</PayEntity>
<DIVISION>CORP</DIVISION>
<ORGANIZATION>GES</ORGANIZATION>
<COMPANYNUMBER>01</COMPANYNUMBER>
<LEDGERDEPARTMENT>CHEN050D</LEDGERDEPARTMENT>
<SALARY_GRADE>LC008</SALARY_GRADE>
<TEMPORARY_POSITION_INDICATOR_FOR_POSITION_RECORD />
<LocationCode>AP10</LocationCode>
<LocationDepartment>050D</LocationDepartment>
<WDEmpID>10032417</WDEmpID>
<Indicator>Position and Location Department change Indicator
</Indicator>
</Record>
</POSITION>
<COMPENSATION />
<SALES_TERRITORY />
<TERMINATION />
</Employee>
</Employee_Data>
This is an xml generated by 1 xslt. I basically want to check if 2 records under Position tab are similar then keep only 1 else keep both of them. In this case the output should be like as given below.
<?xml version="1.0" encoding="utf-8"?>
<Employee_Data>
<Employee>
<NEW_HIRE_OR_REHIRE />
<RETIREMENT_BENEFITS />
<ADDRESS />
<PERSONAL>
<Record>
<SSN>327408678</SSN>
<WDEmpID>10032417</WDEmpID>
<Initiator />
<Effective>20141014</Effective>
<SeqNum>320</SeqNum>
<Last_Name>VAN TREECK</Last_Name>
<First_Name>DENISE</First_Name>
<Middle_Name>J</Middle_Name>
<Social_Suffix />
<Birth_Date>19560422</Birth_Date>
<Gender>F</Gender>
<Ethnicity>0</Ethnicity>
<Marital_Status_Date>19781202</Marital_Status_Date>
<Marital_Status>M</Marital_Status>
<CITIZENSHIP />
<Military_Service_Status />
<Disability />
<Indicator>PersonalRecordChangesIndicator</Indicator>
</Record>
</PERSONAL>
<STATUS />
<POSITION>
<Record>
<SSN>327408678</SSN>
<WDEmpID>10032417</WDEmpID>
<Initiator />
<Effective>20141006</Effective>
<SeqNum>250</SeqNum>
<ActionCode />
<DEFAULTJOBCODE>YYY01</DEFAULTJOBCODE>
<SAPJOBCODE>30000715</SAPJOBCODE>
<PayEntity>NC1</PayEntity>
<DIVISION>CORP</DIVISION>
<ORGANIZATION>GES</ORGANIZATION>
<COMPANYNUMBER>01</COMPANYNUMBER>
<LEDGERDEPARTMENT>CHEN050D</LEDGERDEPARTMENT>
<SALARY_GRADE>LC008</SALARY_GRADE>
<TEMPORARY_POSITION_INDICATOR_FOR_POSITION_RECORD />
<LocationCode>AP10</LocationCode>
<LocationDepartment>050D</LocationDepartment>
<WDEmpID>10032417</WDEmpID>
<Indicator>Position and Location Change Indicator</Indicator>
</Record>
</POSITION>
<COMPENSATION />
<SALES_TERRITORY />
<TERMINATION />
</Employee>
</Employee_Data>

Answer 1

To remove the duplicate records, you can use Muenchian Grouping:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="no" indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:key name="seqNumByRecord" match="Record" use="SeqNum"/>
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<xsl:template match=
"Record[not(generate-id() = generate-id(key('seqNumByRecord', SeqNum)[1]))]"
/>
</xsl:stylesheet>
The first template is an identity transform that matches all attributes and nodes and copies them. The second template is an empty template that matches all duplicates. Because the template is empty, these Records will be removed. For a detailed explanation of Muenchian Grouping this article by Jeni Tennison is recommended: http://www.jenitennison.com/xslt/grouping/muenchian.html, and you will also find many excellent answers on Stackoverflow.
For variety, a second solution:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:strip-space elements="*"/>
<xsl:template match="node()|#*">
<xsl:copy>
<xsl:apply-templates select="node()|#*"/>
</xsl:copy>
</xsl:template>
<xsl:template match="Record[SeqNum = following::Record/SeqNum]"/>
</xsl:stylesheet>
In this approach, the empty template for removing the duplicates matches all Records that have the same SeqNum as following Records. As you'll find in the mentioned article, the Muenchian method is considered to be more efficient.