XMLParser Syntax Elements - Teradata Vantage

[grandparent/]parent/child[,...]

where grandparent, parent, and child are node names.

For each grandparent, parent, and child, you can specify one or more attributes to extract:

{grandparent|parent|child}[:attribute[,...]]

For each node_pair_string, the function creates a row in the output table and adds a column for each specified attribute.

A grandparent or parent without attributes can contain wildcards. The wildcards can follow the rules of either the SQL LIKE statement or the Java regular expression.

For example, 'like(%a_c\_)/d' matches the XML fragment <123abc_><d>text</d></123abc_>.

The Java Regular Expression syntax is 'regex( expression )', where expression follows the rules for a Java regular expression.

If no node_pair_string contains a parent node, or no node_pair_string contains a grandparent node, the function outputs nothing. If no node_pair_string contains a child node, the function outputs NULL child node values. If the syntax element specifies no attributes, the function outputs NULL attribute values.

sibling_node_name[:attribute[,...]]

The function includes the values from the sibling nodes in every output row and adds a column to the output table for every sibling node and every specified attribute.

If no sibling_node_string contains a sibling node, the function outputs NULL sibling node values. If the syntax element specifies no attributes, the function outputs NULL attribute values.

node[/node]...

For each node, you can specify one or more attributes:

node[:attribute[,...]]

A node without attributes can contain wildcards. The wildcards can follow the rules of either the SQL LIKE statement or the Java regular expression. For details, see the description of the Node syntax element.

If you specify multiple ancestor paths, the function parses each XML document to get results for each ancestor path. If different ancestor paths contain duplicate node names, as in the following example, the result can be ambiguous:

SELECT * FROM xmlparser (
  ON xml_inputstext_column ('xml')
  Nodes ('parent1/child1')
  Ancestor ('A/B:attr/C:attr','A/C:attr/B:attr')
);