You can get online Help for the Hive extension functions by using this command:
DESCRIBE FUNCTION [EXTENDED] function_name;
This example provides a brief description of the xml_query
function:
hive> describe function xml_query;
OK
xml_query(query, bindings) - Returns the result of the query as a STRING array
The EXTENDED
option provides a detailed description and examples:
hive> describe function extended xml_query;
OK
xml_query(query, bindings) - Returns the result of the query as a STRING array
Evaluates an XQuery expression with the specified bindings. The query argument must be a STRING and the bindings argument must be a STRING or a STRUCT. If the bindings argument is a STRING, it is parsed as XML and bound to the initial context item of the query. For example:
> SELECT xml_query("x/y", "<x><y>hello</y><z/><y>world</y></x>") FROM src LIMIT 1;
["hello", "world"]
.
.
.