[HIVE-1027] Create UDFs for XPath expression evaluation

• Type: New Feature
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 0.6.0
• Component/s: Query Processor
• Assignee: Patrick Angeles
• Reporter: Patrick Angeles
• Created: 05/Jan/10 05:12
• Updated: 17/Dec/11 00:04
• Resolved: 15/Mar/10 06:11

Description

Create UDFs for evaluating XPath expressions against XML documents.

Examples:

> SELECT xpath_double ('<a><b class="odd">1</b><b class="even">2</b><b class="odd">4</b><c>8</c></a>', 'sum(a/b[@class="odd"])') FROM src LIMIT 1 ;
5.0
> SELECT xpath_string ('<a><b>b1</b><b>b2</b></a>', 'a/b[2]') FROM src LIMIT 1 ;
b2
> SELECT xpath ('<a><b>b1</b><b>b2</b><b>b3</b><c>c1</c><c>c2</c></a>', 'a/c/text()') FROM src LIMIT 1 ;
["c1","c2"]

Included functions are: xpath_short, xpath_int, xpath_long, xpath_float, xpath_double/xpath_number, xpath_string, xpath