Regenerating text documents from the Java-based XQL processor

This section demonstrates regenerating the text form of the documents from the form generated for the Java-based XQL processor.

If the xmlindexed column contains sybase.aseutils.SybXmlStream data generated by com.sybase.xmlxql.Xql.parse, you can regenerate the text form of the document in the new xmlsource column with the following SQL statement:

update xmltab
set xmlsource
   = xmlextract("/xql_result/*",
      com.sybase.xml.xql.Xql.query("/",xmlindexed) )

This statement generates text form of the document in two steps:

1. The com.sybase.xml.xql.Xql.query call with the "/" query generates a text form of the document, enclosed in an XML tag <xql_result>...</xql_result>.

2. The xmlextract call with the "/xql_result/*" query removes the <xql_result>...</xql_result> tag, and returns the text form of the original document.

You can then process the xmlsource column directly with the native XML processor, using the xmlextract and xmltest built-in functions, or you can update the xmlindexed column for the native XML processor, as follows:

update xmltab
set xmlindexed = xmlparse(xmlsource)

If you don't want to add the xmlsource column, you can combine these steps, as in the following SQL statement:

update xmltab
set xmlindexed
  = xmlparse(xmlextract("/xql_result/*",
      com.sybase.xml.xql.Xql.query("/",xmlindexed) ) )

Before this update statement is executed, the xmlindexed column contains the sybase.aseutiles.SybXmlStream form of the documents, generated by the com.sybase.xml.xql.Xql.parse method. After the update statement, that column contains the parsed form of the documents, suitable for processing with the xmlextract and xmlparse methods.