使用xslt从xml中删除重复项

Question

How to remove duplicates from the below xml using xslt. Below is the code am using. It works fine for removing the duplicates but am not able to add the corresponding values

    <schedules>
       <flight>
      <Flight>
      <fno>122</fno>
      <acode>aa</acode>
        <Dest1IATA>ATL</Dest1IATA>  
        <Dest1desc>Atlanta Airport</Dest1desc>
        <Dest1town>Atlanta </Dest1town>
        <Dest2IATA>JFK</Dest2IATA>           
        <Dest2desc></Dest2desc>
        <Dest2town></Dest2town>
        <Dest2cntry></Dest2cntry>            
        <Dest3IATA>LGA</Dest3IATA>           
        <Dest3desc></Dest3desc>
        <Dest3town></Dest3town>
        <Dest3cntry></Dest3cntry>
        </Flight>
          <Flight>
      <fno>124</fno>
      <acode>aB</acode>
        <Dest1IATA>LCY</Dest1IATA>  
        <Dest1desc>LCY Airport</Dest1desc>
        <Dest1town>LCY</Dest1town>
        <Dest2IATA>DXB</Dest2IATA>           
        <Dest2desc></Dest2desc>
        <Dest2town></Dest2town>
        <Dest2cntry></Dest2cntry>            
        <Dest3IATA>LGA</Dest3IATA>           
        <Dest3desc></Dest3desc>
        <Dest3town></Dest3town>
        <Dest3cntry></Dest3cntry>
        </Flight>         
        </flight>
        </schedules>

Xslt code:

     <xsl:for-each select="(//schedules/flight/Flight/Dest1IATA | //schedules/flight/Flight/Dest2IATA | //schedules/flight/Flight/Dest3IATA)[generate-id(.) = generate-id(key('Keycity', .))]">
      <xsl:sort select="//schedules/flight/Flight/Dest1IATA | //schedules/flight/Flight/Dest2IATA | //schedules/flight/Flight/Dest3IATA"/>

      <!--<xsl:value-of select="." />-->
      <xsl:if test="local-name() = 'Dest1IATA'  and //schedules/flight/Flight/Dest1IATA != ''">
        <Row Action="ADD">
          <xsl:value-of select="." />|<xsl:value-of select="//schedules/flight/Flight/Dest1desc" />|<xsl:value-of  select="//schedules/flight/Flight/Dest1town" />|<xsl:value-of  select="//schedules/flight/Flight/Dest1cntry" />
        </Row>
      </xsl:if>
      <xsl:if test="local-name() = 'Dest2IATA'  and //schedules/flight/Flight/Dest2IATA != ''">
        <Row Action="ADD">
          <xsl:value-of select="." />|<xsl:value-of select="//schedules/flight/Flight/Dest2desc" />|<xsl:value-of  select="//schedules/flight/Flight/Dest2town" />|<xsl:value-of  select="//schedules/flight/Flight/Dest2cntry" />
        </Row>
      </xsl:if>
      <xsl:if test="local-name() = 'Dest3IATA'  and //schedules/flight/Flight/Dest3IATA != ''">
        <Row Action="ADD">
          <xsl:value-of select="." />|<xsl:value-of select="//schedules/flight/Flight/Dest3desc" />|<xsl:value-of  select="//schedules/flight/Flight/Dest3town" />|<xsl:value-of  select="//schedules/flight/Flight/Dest3cntry" />
        </Row>
      </xsl:if>
    </xsl:for-each>

ExpectedOutput should be

ROW|Add|ATL|Atlanta Airport|
ROW|Add|JFK||
ROW|Add|LGA||
ROW|Add|LCY|LCYAirport|LCY
ROW|Add|DXB||

Output with above Code

ROW|Add|ATL||
ROW|Add|JFK||
ROW|Add|LGA||
ROW|Add|LCY||
ROW|Add|DXB||

Answer 1

The following stylesheet produces an output quite similar to what you expect. It could be a lucky guess or just a coincidence.

XSLT 1.0

<xsl:stylesheet version="1.0" 
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" encoding="UTF-8"/>

<xsl:key name="dest" match="Dest1IATA | Dest2IATA | Dest3IATA" use="." />

<xsl:template match="/schedules">
    <xsl:for-each select="(flight/Flight/Dest1IATA | flight/Flight/Dest2IATA | flight/Flight/Dest3IATA)[generate-id(.) = generate-id(key('dest', .))]">
        <xsl:text>ROW|Add|</xsl:text>
        <xsl:value-of select="." />
        <xsl:if test="self::Dest1IATA">
            <xsl:text>|</xsl:text>
            <xsl:value-of select="../Dest1desc" />
            <xsl:text>|</xsl:text>
            <xsl:value-of select="../Dest1town" />      
        </xsl:if>
        <xsl:text>&#10;</xsl:text>
    </xsl:for-each> 
</xsl:template>

</xsl:stylesheet>

Applied to your input example, the result will be:

ROW|Add|ATL|Atlanta Airport|Atlanta 
ROW|Add|JFK
ROW|Add|LGA
ROW|Add|LCY|LCY Airport|LCY
ROW|Add|DXB