Any way to generate a single quote (') with XSLT?

Question

Hi:
I guess this is really an XSLT question. I'm using the Transform() method of an XMLType variable to apply a style sheet. The XML in the variable is just something simple like
<TBL>
<LAST_NAME>LIKE|JONES</LAST_NAME>
<FIRST_NAME>=|MARY</FIRST_NAME>
<AGE>=|50</AGE>
</TBL>
I am trying to get a stylesheet to transform something like the above into SQL such as
Select * from foo where LAST_NAME like 'JONES'
and FIRST_NAME ='MARY'
and AGE = 50But to do this, I need to generate the single quotes around the search terms and I can't get anything but LAST_NAME LIKE &apos;JONES&apos;. Is there a way to do this? For now I am generating a ~ and replacing ~ for ' throughout the generated SQL text but that's a pretty sorry solution.
I thought that something like <xsl:text disable-output-escaping="yes">&amp;</xsl:text> was going to work but then found out it has been deprecated. I was thinking character-map might work but that's an XSLT 2.0 thing and apparently 10g is on XSLT 1.0? In any case, it had no idea what I was trying to do with a character map.
So, am I overlooking an obvious way to get my stylesheet to insert apostrophes?
Thanks.

Answer 1

It's 10.2.0.4.
Here's the procedure that accepts the XML/XSL clobs and tries to produce a SQL statement.
PROCEDURE GetSQLQueryFromXML(XMLClob in CLOB, XSLStylesheet in CLOB,
            SQLQuery out CLOB, status out integer) IS
    -- Define the local variables
  xmldata               XMLType;  -- The XMLType format of the XML to transform
  xsldata               XMLType;  -- The XMLType format of the stylesheet to apply
  sqlQuery_XMLType      XMLType;  -- The XMLType format of the SQL query.
  v_SQLQuery            Clob;     -- Holds XML Clob before translating ~ to '
BEGIN
status := -1;  -- Initially unsuccessful
  -- Get the XML document using the getXML() function defined in the database.
  -- Since XMLType.transform() method takes XML data as XMLType instance,
  -- use the XMLType.createXML method to convert the XML content received
  -- as CLOB into an XMLType instance.
  xmldata := XMLType.createXML(XMLClob);
  -- Get the XSL Stylesheet using the getXSL() function defined in the database.
  -- Since XMLType.transform() method takes an XSL stylesheet as XMLType instance,
  -- use the XMLType.createXML method to convert the XSL content received as CLOB
  -- into an XMLType instance.
  xsldata := XMLType.createXML(XSLStylesheet);
  -- Use the XMLtype.transform() function to get the transformed XML instance.
  -- This function applies the stylesheet to the XML document and returns a transformed
  -- XML instance.
  sqlQuery_XMLType := xmldata.transform(xsldata);
  -- Return the transformed XML instance as a CLOB value.   
  v_SQLQuery := sqlQuery_XMLType.getClobVal();
  -- Change tildas to apostrophes.  Currently unable to get an XSLT transformation
  -- to insert single quotes, so we're inserting ~ instead.  Now we need to
  -- translate all ~s to 's in our query.
  SQLQuery := translate(to_char(v_SQLQuery),'~','''');
  status := 1; -- Everything went fine to get here
EXCEPTION
  WHEN OTHERS THEN         
    raise_application_error
    (-20102, 'Exception occurred in GetSQLQueryFromXML :'||SQLERRM);
END GetSQLQueryFromXML;The XML it works off of is
    someXML CLOB :=
    to_clob('<?xml version="1.0" encoding="windows-1252" ?>
<variable table_name="SOME_PERSON_TABLE" query_type="PERSON">
  <item>
    <fieldName><![CDATA[PERSON_KEY]]></fieldName>
    <criteria><![CDATA[=]]></criteria>
    <fieldType><![CDATA[Integer]]></fieldType>
    <value><![CDATA[123456789]]></value>
  </item>
  <item>
    <fieldName><![CDATA[LAST_NAME]]></fieldName>
    <criteria><![CDATA[=]]></criteria>
    <fieldType><![CDATA[String]]></fieldType>
    <value><![CDATA[DOE]]></value>
  </item>
  <item>
    <fieldName><![CDATA[FIRST_NAME]]></fieldName>
    <criteria><![CDATA[=]]></criteria>
    <fieldType><![CDATA[String]]></fieldType>
    <value><![CDATA[JOHN]]></value>
  </item>
  <item>
    <fieldName><![CDATA[MIDDLE_NAME]]></fieldName>
    <criteria><![CDATA[-]]></criteria>
    <fieldType><![CDATA[String]]></fieldType>
    <value />
  </item>
  <item>
    <fieldName><![CDATA[SUFFIX]]></fieldName>
    <criteria><![CDATA[-]]></criteria>
    <fieldType><![CDATA[String]]></fieldType>
    <value />
  </item>
</variable>');And the corresponding XSLT that should translate it is:
  myStylesheet  CLOB :=
  to_clob('<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<!-- <xsl:preserve-space elements="list-of-element-names"/> -->
  <!-- We just want the SQL text output.  No XML declaration etc. -->
  <xsl:output method="text" omit-xml-declaration="yes" indent="no"/>
<!-- Apostrophes will be made tildas and the PL/SQL will translate those to -->
<!-- apostrophes for the final SQL string. -->
<xsl:variable name="apos">~</xsl:variable>
  <xsl:template match="/">
    select * from
    <xsl:value-of select="variable/@table_name"/>
    where 1=1
    <xsl:for-each select="variable/child::node()">
      <xsl:choose>
        <!-- if the value node is not null... -->
        <xsl:when test="./value/text()[normalize-space(.)]">
        <!-- There is another predicate.  Add the AND term and the predicate -->
          AND <xsl:value-of select="./fieldName"/>
          <xsl:text> </xsl:text>
          <xsl:value-of select="./criteria"/>
          <xsl:text> </xsl:text>       
          <xsl:choose>
            <xsl:when test="string(./fieldType)=''String''">
              <xsl:copy-of select="$apos" />
              <xsl:value-of select="./value"/>
              <xsl:copy-of select="$apos" />
            </xsl:when>         
            <xsl:when test="string(./fieldType)=''Clob''">
              <xsl:copy-of select="$apos" />
              <xsl:value-of select="./value"/>
              <xsl:copy-of select="$apos" />
            </xsl:when>
            <xsl:otherwise>
              <xsl:value-of select="./value"/>
            </xsl:otherwise>
          </xsl:choose>
        </xsl:when>
      </xsl:choose>
    </xsl:for-each>
  </xsl:template>
</xsl:stylesheet>');Basically if the VALUE element has a value then the fieldType is checked. If fieldType is String or Clob then we'll need the apostrophes. For now I'm putting in tildas and changing them later.