ydb/yql/essentials/tests/postgresql/original/cases/xml_2.out

CREATE TABLE xmltest (
    id int,
    data xml
);
INSERT INTO xmltest VALUES (1, '<value>one</value>');
INSERT INTO xmltest VALUES (2, '<value>two</value>');
INSERT INTO xmltest VALUES (3, '<wrong');
ERROR:  invalid XML content
LINE 1: INSERT INTO xmltest VALUES (3, '<wrong');
                                       ^
DETAIL:  line 1: Couldn't find end of Start Tag wrong line 1
SELECT * FROM xmltest;
 id |        data        
----+--------------------
  1 | <value>one</value>
  2 | <value>two</value>
(2 rows)

SELECT xmlcomment('test');
 xmlcomment  
-------------
 <!--test-->
(1 row)

SELECT xmlcomment('-test');
  xmlcomment  
--------------
 <!---test-->
(1 row)

SELECT xmlcomment('test-');
ERROR:  invalid XML comment
SELECT xmlcomment('--test');
ERROR:  invalid XML comment
SELECT xmlcomment('te st');
  xmlcomment  
--------------
 <!--te st-->
(1 row)

SELECT xmlconcat(xmlcomment('hello'),
                 xmlelement(NAME qux, 'foo'),
                 xmlcomment('world'));
               xmlconcat                
----------------------------------------
 <!--hello--><qux>foo</qux><!--world-->
(1 row)

SELECT xmlconcat('hello', 'you');
 xmlconcat 
-----------
 helloyou
(1 row)

SELECT xmlconcat(1, 2);
ERROR:  argument of XMLCONCAT must be type xml, not type integer
LINE 1: SELECT xmlconcat(1, 2);
                         ^
SELECT xmlconcat('bad', '<syntax');
ERROR:  invalid XML content
LINE 1: SELECT xmlconcat('bad', '<syntax');
                                ^
DETAIL:  line 1: Couldn't find end of Start Tag syntax line 1
SELECT xmlconcat('<foo/>', NULL, '<?xml version="1.1" standalone="no"?><bar/>');
  xmlconcat   
--------------
 <foo/><bar/>
(1 row)

SELECT xmlconcat('<?xml version="1.1"?><foo/>', NULL, '<?xml version="1.1" standalone="no"?><bar/>');
             xmlconcat             
-----------------------------------
 <?xml version="1.1"?><foo/><bar/>
(1 row)

SELECT xmlconcat(NULL);
 xmlconcat 
-----------
 
(1 row)

SELECT xmlconcat(NULL, NULL);
 xmlconcat 
-----------
 
(1 row)

SELECT xmlelement(name element,
                  xmlattributes (1 as one, 'deuce' as two),
                  'content');
                   xmlelement                   
------------------------------------------------
 <element one="1" two="deuce">content</element>
(1 row)

SELECT xmlelement(name element,
                  xmlattributes ('unnamed and wrong'));
ERROR:  unnamed XML attribute value must be a column reference
LINE 2:                   xmlattributes ('unnamed and wrong'));
                                         ^
SELECT xmlelement(name element, xmlelement(name nested, 'stuff'));
                xmlelement                 
-------------------------------------------
 <element><nested>stuff</nested></element>
(1 row)

SELECT xmlelement(name employee, xmlforest(name, age, salary as pay)) FROM emp;
                              xmlelement                              
----------------------------------------------------------------------
 <employee><name>sharon</name><age>25</age><pay>1000</pay></employee>
 <employee><name>sam</name><age>30</age><pay>2000</pay></employee>
 <employee><name>bill</name><age>20</age><pay>1000</pay></employee>
 <employee><name>jeff</name><age>23</age><pay>600</pay></employee>
 <employee><name>cim</name><age>30</age><pay>400</pay></employee>
 <employee><name>linda</name><age>19</age><pay>100</pay></employee>
(6 rows)

SELECT xmlelement(name duplicate, xmlattributes(1 as a, 2 as b, 3 as a));
ERROR:  XML attribute name "a" appears more than once
LINE 1: ...ment(name duplicate, xmlattributes(1 as a, 2 as b, 3 as a));
                                                              ^
SELECT xmlelement(name num, 37);
  xmlelement   
---------------
 <num>37</num>
(1 row)

SELECT xmlelement(name foo, text 'bar');
   xmlelement   
----------------
 <foo>bar</foo>
(1 row)

SELECT xmlelement(name foo, xml 'bar');
   xmlelement   
----------------
 <foo>bar</foo>
(1 row)

SELECT xmlelement(name foo, text 'b<a/>r');
       xmlelement        
-------------------------
 <foo>b&lt;a/&gt;r</foo>
(1 row)

SELECT xmlelement(name foo, xml 'b<a/>r');
    xmlelement     
-------------------
 <foo>b<a/>r</foo>
(1 row)

SELECT xmlelement(name foo, array[1, 2, 3]);
                               xmlelement                                
-------------------------------------------------------------------------
 <foo><element>1</element><element>2</element><element>3</element></foo>
(1 row)

SET xmlbinary TO base64;
SELECT xmlelement(name foo, bytea 'bar');
   xmlelement    
-----------------
 <foo>YmFy</foo>
(1 row)

SET xmlbinary TO hex;
SELECT xmlelement(name foo, bytea 'bar');
    xmlelement     
-------------------
 <foo>626172</foo>
(1 row)

SELECT xmlelement(name foo, xmlattributes(true as bar));
    xmlelement     
-------------------
 <foo bar="true"/>
(1 row)

SELECT xmlelement(name foo, xmlattributes('2009-04-09 00:24:37'::timestamp as bar));
            xmlelement            
----------------------------------
 <foo bar="2009-04-09T00:24:37"/>
(1 row)

SELECT xmlelement(name foo, xmlattributes('infinity'::timestamp as bar));
ERROR:  timestamp out of range
DETAIL:  XML does not support infinite timestamp values.
SELECT xmlelement(name foo, xmlattributes('<>&"''' as funny, xml 'b<a/>r' as funnier));
                         xmlelement                         
------------------------------------------------------------
 <foo funny="&lt;&gt;&amp;&quot;'" funnier="b&lt;a/&gt;r"/>
(1 row)

SELECT xmlparse(content '');
 xmlparse 
----------
 
(1 row)

SELECT xmlparse(content '  ');
 xmlparse 
----------
   
(1 row)

SELECT xmlparse(content 'abc');
 xmlparse 
----------
 abc
(1 row)

SELECT xmlparse(content '<abc>x</abc>');
   xmlparse   
--------------
 <abc>x</abc>
(1 row)

SELECT xmlparse(content '<invalidentity>&</invalidentity>');
ERROR:  invalid XML content
DETAIL:  line 1: xmlParseEntityRef: no name
<invalidentity>&</invalidentity>
                ^
line 1: chunk is not well balanced
SELECT xmlparse(content '<undefinedentity>&idontexist;</undefinedentity>');
ERROR:  invalid XML content
DETAIL:  line 1: Entity 'idontexist' not defined
<undefinedentity>&idontexist;</undefinedentity>
                             ^
line 1: chunk is not well balanced
SELECT xmlparse(content '<invalidns xmlns=''&lt;''/>');
         xmlparse          
---------------------------
 <invalidns xmlns='&lt;'/>
(1 row)

SELECT xmlparse(content '<relativens xmlns=''relative''/>');
            xmlparse            
--------------------------------
 <relativens xmlns='relative'/>
(1 row)

SELECT xmlparse(content '<twoerrors>&idontexist;</unbalanced>');
ERROR:  invalid XML content
DETAIL:  line 1: Entity 'idontexist' not defined
<twoerrors>&idontexist;</unbalanced>
                       ^
line 1: Opening and ending tag mismatch: twoerrors line 1 and unbalanced
line 1: chunk is not well balanced
SELECT xmlparse(content '<nosuchprefix:tag/>');
      xmlparse       
---------------------
 <nosuchprefix:tag/>
(1 row)

SELECT xmlparse(document '   ');
ERROR:  invalid XML document
DETAIL:  line 1: Start tag expected, '<' not found
SELECT xmlparse(document 'abc');
ERROR:  invalid XML document
DETAIL:  line 1: Start tag expected, '<' not found
abc
^
SELECT xmlparse(document '<abc>x</abc>');
   xmlparse   
--------------
 <abc>x</abc>
(1 row)

SELECT xmlparse(document '<invalidentity>&</abc>');
ERROR:  invalid XML document
DETAIL:  line 1: xmlParseEntityRef: no name
<invalidentity>&</abc>
                ^
line 1: Opening and ending tag mismatch: invalidentity line 1 and abc
SELECT xmlparse(document '<undefinedentity>&idontexist;</abc>');
ERROR:  invalid XML document
DETAIL:  line 1: Entity 'idontexist' not defined
<undefinedentity>&idontexist;</abc>
                             ^
line 1: Opening and ending tag mismatch: undefinedentity line 1 and abc
SELECT xmlparse(document '<invalidns xmlns=''&lt;''/>');
         xmlparse          
---------------------------
 <invalidns xmlns='&lt;'/>
(1 row)

SELECT xmlparse(document '<relativens xmlns=''relative''/>');
            xmlparse            
--------------------------------
 <relativens xmlns='relative'/>
(1 row)

SELECT xmlparse(document '<twoerrors>&idontexist;</unbalanced>');
ERROR:  invalid XML document
DETAIL:  line 1: Entity 'idontexist' not defined
<twoerrors>&idontexist;</unbalanced>
                       ^
line 1: Opening and ending tag mismatch: twoerrors line 1 and unbalanced
SELECT xmlparse(document '<nosuchprefix:tag/>');
      xmlparse       
---------------------
 <nosuchprefix:tag/>
(1 row)

SELECT xmlpi(name foo);
  xmlpi  
---------
 <?foo?>
(1 row)

SELECT xmlpi(name xml);
ERROR:  invalid XML processing instruction
DETAIL:  XML processing instruction target name cannot be "xml".
SELECT xmlpi(name xmlstuff);
    xmlpi     
--------------
 <?xmlstuff?>
(1 row)

SELECT xmlpi(name foo, 'bar');
    xmlpi    
-------------
 <?foo bar?>
(1 row)

SELECT xmlpi(name foo, 'in?>valid');
ERROR:  invalid XML processing instruction
DETAIL:  XML processing instruction cannot contain "?>".
SELECT xmlpi(name foo, null);
 xmlpi 
-------
 
(1 row)

SELECT xmlpi(name xml, null);
ERROR:  invalid XML processing instruction
DETAIL:  XML processing instruction target name cannot be "xml".
SELECT xmlpi(name xmlstuff, null);
 xmlpi 
-------
 
(1 row)

SELECT xmlpi(name "xml-stylesheet", 'href="mystyle.css" type="text/css"');
                         xmlpi                         
-------------------------------------------------------
 <?xml-stylesheet href="mystyle.css" type="text/css"?>
(1 row)

SELECT xmlpi(name foo, '   bar');
    xmlpi    
-------------
 <?foo bar?>
(1 row)

SELECT xmlroot(xml '<foo/>', version no value, standalone no value);
 xmlroot 
---------
 <foo/>
(1 row)

SELECT xmlroot(xml '<foo/>', version '2.0');
           xmlroot           
-----------------------------
 <?xml version="2.0"?><foo/>
(1 row)

SELECT xmlroot(xml '<foo/>', version no value, standalone yes);
                   xmlroot                    
----------------------------------------------
 <?xml version="1.0" standalone="yes"?><foo/>
(1 row)

SELECT xmlroot(xml '<?xml version="1.1"?><foo/>', version no value, standalone yes);
                   xmlroot                    
----------------------------------------------
 <?xml version="1.0" standalone="yes"?><foo/>
(1 row)

SELECT xmlroot(xmlroot(xml '<foo/>', version '1.0'), version '1.1', standalone no);
                   xmlroot                   
---------------------------------------------
 <?xml version="1.1" standalone="no"?><foo/>
(1 row)

SELECT xmlroot('<?xml version="1.1" standalone="yes"?><foo/>', version no value, standalone no);
                   xmlroot                   
---------------------------------------------
 <?xml version="1.0" standalone="no"?><foo/>
(1 row)

SELECT xmlroot('<?xml version="1.1" standalone="yes"?><foo/>', version no value, standalone no value);
 xmlroot 
---------
 <foo/>
(1 row)

SELECT xmlroot('<?xml version="1.1" standalone="yes"?><foo/>', version no value);
                   xmlroot                    
----------------------------------------------
 <?xml version="1.0" standalone="yes"?><foo/>
(1 row)

SELECT xmlroot (
  xmlelement (
    name gazonk,
    xmlattributes (
      'val' AS name,
      1 + 1 AS num
    ),
    xmlelement (
      NAME qux,
      'foo'
    )
  ),
  version '1.0',
  standalone yes
);
                                         xmlroot                                          
------------------------------------------------------------------------------------------
 <?xml version="1.0" standalone="yes"?><gazonk name="val" num="2"><qux>foo</qux></gazonk>
(1 row)

SELECT xmlserialize(content data as character varying(20)) FROM xmltest;
    xmlserialize    
--------------------
 <value>one</value>
 <value>two</value>
(2 rows)

SELECT xmlserialize(content 'good' as char(10));
 xmlserialize 
--------------
 good      
(1 row)

SELECT xmlserialize(document 'bad' as text);
ERROR:  not an XML document
SELECT xml '<foo>bar</foo>' IS DOCUMENT;
 ?column? 
----------
 t
(1 row)

SELECT xml '<foo>bar</foo><bar>foo</bar>' IS DOCUMENT;
 ?column? 
----------
 f
(1 row)

SELECT xml '<abc/>' IS NOT DOCUMENT;
 ?column? 
----------
 f
(1 row)

SELECT xml 'abc' IS NOT DOCUMENT;
 ?column? 
----------
 t
(1 row)

SELECT '<>' IS NOT DOCUMENT;
ERROR:  invalid XML content
LINE 1: SELECT '<>' IS NOT DOCUMENT;
               ^
DETAIL:  line 1: StartTag: invalid element name
<>
 ^
SELECT xmlagg(data) FROM xmltest;
                xmlagg                
--------------------------------------
 <value>one</value><value>two</value>
(1 row)

SELECT xmlagg(data) FROM xmltest WHERE id > 10;
 xmlagg 
--------
 
(1 row)

SELECT xmlelement(name employees, xmlagg(xmlelement(name name, name))) FROM emp;
                                                           xmlelement                                                           
--------------------------------------------------------------------------------------------------------------------------------
 <employees><name>sharon</name><name>sam</name><name>bill</name><name>jeff</name><name>cim</name><name>linda</name></employees>
(1 row)

-- Check mapping SQL identifier to XML name
SELECT xmlpi(name ":::_xml_abc135.%-&_");
                      xmlpi                      
-------------------------------------------------
 <?_x003A_::_x005F_xml_abc135._x0025_-_x0026__?>
(1 row)

SELECT xmlpi(name "123");
     xmlpi     
---------------
 <?_x0031_23?>
(1 row)

PREPARE foo (xml) AS SELECT xmlconcat('<foo/>', $1);
SET XML OPTION DOCUMENT;
EXECUTE foo ('<bar/>');
  xmlconcat   
--------------
 <foo/><bar/>
(1 row)

EXECUTE foo ('bad');
ERROR:  invalid XML document
LINE 1: EXECUTE foo ('bad');
                     ^
DETAIL:  line 1: Start tag expected, '<' not found
bad
^
SELECT xml '<!DOCTYPE a><a/><b/>';
ERROR:  invalid XML document
LINE 1: SELECT xml '<!DOCTYPE a><a/><b/>';
                   ^
DETAIL:  line 1: Extra content at the end of the document
<!DOCTYPE a><a/><b/>
                ^
SET XML OPTION CONTENT;
EXECUTE foo ('<bar/>');
  xmlconcat   
--------------
 <foo/><bar/>
(1 row)

EXECUTE foo ('good');
 xmlconcat  
------------
 <foo/>good
(1 row)

SELECT xml '<!-- in SQL:2006+ a doc is content too--> <?y z?> <!DOCTYPE a><a/>';
                                xml                                 
--------------------------------------------------------------------
 <!-- in SQL:2006+ a doc is content too--> <?y z?> <!DOCTYPE a><a/>
(1 row)

SELECT xml '<?xml version="1.0"?> <!-- hi--> <!DOCTYPE a><a/>';
             xml              
------------------------------
  <!-- hi--> <!DOCTYPE a><a/>
(1 row)

SELECT xml '<!DOCTYPE a><a/>';
       xml        
------------------
 <!DOCTYPE a><a/>
(1 row)

SELECT xml '<!-- hi--> oops <!DOCTYPE a><a/>';
ERROR:  invalid XML content
LINE 1: SELECT xml '<!-- hi--> oops <!DOCTYPE a><a/>';
                   ^
DETAIL:  line 1: StartTag: invalid element name
<!-- hi--> oops <!DOCTYPE a><a/>
                 ^
SELECT xml '<!-- hi--> <oops/> <!DOCTYPE a><a/>';
ERROR:  invalid XML content
LINE 1: SELECT xml '<!-- hi--> <oops/> <!DOCTYPE a><a/>';
                   ^
DETAIL:  line 1: StartTag: invalid element name
<!-- hi--> <oops/> <!DOCTYPE a><a/>
                    ^
SELECT xml '<!DOCTYPE a><a/><b/>';
ERROR:  invalid XML content
LINE 1: SELECT xml '<!DOCTYPE a><a/><b/>';
                   ^
DETAIL:  line 1: Extra content at the end of the document
<!DOCTYPE a><a/><b/>
                ^
-- Test backwards parsing
CREATE VIEW xmlview1 AS SELECT xmlcomment('test');
CREATE VIEW xmlview2 AS SELECT xmlconcat('hello', 'you');
CREATE VIEW xmlview3 AS SELECT xmlelement(name element, xmlattributes (1 as ":one:", 'deuce' as two), 'content&');
CREATE VIEW xmlview4 AS SELECT xmlelement(name employee, xmlforest(name, age, salary as pay)) FROM emp;
CREATE VIEW xmlview5 AS SELECT xmlparse(content '<abc>x</abc>');
CREATE VIEW xmlview6 AS SELECT xmlpi(name foo, 'bar');
CREATE VIEW xmlview7 AS SELECT xmlroot(xml '<foo/>', version no value, standalone yes);
CREATE VIEW xmlview8 AS SELECT xmlserialize(content 'good' as char(10));
CREATE VIEW xmlview9 AS SELECT xmlserialize(content 'good' as text);
SELECT table_name, view_definition FROM information_schema.views
  WHERE table_name LIKE 'xmlview%' ORDER BY 1;
 table_name |                                                  view_definition                                                  
------------+-------------------------------------------------------------------------------------------------------------------
 xmlview1   |  SELECT xmlcomment('test'::text) AS xmlcomment;
 xmlview2   |  SELECT XMLCONCAT('hello'::xml, 'you'::xml) AS "xmlconcat";
 xmlview3   |  SELECT XMLELEMENT(NAME element, XMLATTRIBUTES(1 AS ":one:", 'deuce' AS two), 'content&') AS "xmlelement";
 xmlview4   |  SELECT XMLELEMENT(NAME employee, XMLFOREST(emp.name AS name, emp.age AS age, emp.salary AS pay)) AS "xmlelement"+
            |    FROM emp;
 xmlview5   |  SELECT XMLPARSE(CONTENT '<abc>x</abc>'::text STRIP WHITESPACE) AS "xmlparse";
 xmlview6   |  SELECT XMLPI(NAME foo, 'bar'::text) AS "xmlpi";
 xmlview7   |  SELECT XMLROOT('<foo/>'::xml, VERSION NO VALUE, STANDALONE YES) AS "xmlroot";
 xmlview8   |  SELECT (XMLSERIALIZE(CONTENT 'good'::xml AS character(10)))::character(10) AS "xmlserialize";
 xmlview9   |  SELECT XMLSERIALIZE(CONTENT 'good'::xml AS text) AS "xmlserialize";
(9 rows)

-- Text XPath expressions evaluation
SELECT xpath('/value', data) FROM xmltest;
        xpath         
----------------------
 {<value>one</value>}
 {<value>two</value>}
(2 rows)

SELECT xpath(NULL, NULL) IS NULL FROM xmltest;
 ?column? 
----------
 t
 t
(2 rows)

SELECT xpath('', '<!-- error -->');
ERROR:  empty XPath expression
CONTEXT:  SQL function "xpath" statement 1
SELECT xpath('//text()', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>');
     xpath      
----------------
 {"number one"}
(1 row)

SELECT xpath('//loc:piece/@id', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
 xpath 
-------
 {1,2}
(1 row)

SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
                                                                     xpath                                                                      
------------------------------------------------------------------------------------------------------------------------------------------------
 {"<local:piece xmlns:local=\"http://127.0.0.1\" id=\"1\">number one</local:piece>","<local:piece xmlns:local=\"http://127.0.0.1\" id=\"2\"/>"}
(1 row)

SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1" xmlns="http://127.0.0.2"><local:piece id="1"><internal>number one</internal><internal2/></local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
                                                                                                   xpath                                                                                                    
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 {"<local:piece xmlns:local=\"http://127.0.0.1\" xmlns=\"http://127.0.0.2\" id=\"1\"><internal>number one</internal><internal2/></local:piece>","<local:piece xmlns:local=\"http://127.0.0.1\" id=\"2\"/>"}
(1 row)

SELECT xpath('//b', '<a>one <b>two</b> three <b>etc</b></a>');
          xpath          
-------------------------
 {<b>two</b>,<b>etc</b>}
(1 row)

SELECT xpath('//text()', '<root>&lt;</root>');
 xpath  
--------
 {&lt;}
(1 row)

SELECT xpath('//@value', '<root value="&lt;"/>');
 xpath  
--------
 {&lt;}
(1 row)

SELECT xpath('''<<invalid>>''', '<root/>');
           xpath           
---------------------------
 {&lt;&lt;invalid&gt;&gt;}
(1 row)

SELECT xpath('count(//*)', '<root><sub/><sub/></root>');
 xpath 
-------
 {3}
(1 row)

SELECT xpath('count(//*)=0', '<root><sub/><sub/></root>');
  xpath  
---------
 {false}
(1 row)

SELECT xpath('count(//*)=3', '<root><sub/><sub/></root>');
 xpath  
--------
 {true}
(1 row)

SELECT xpath('name(/*)', '<root><sub/><sub/></root>');
 xpath  
--------
 {root}
(1 row)

SELECT xpath('/nosuchtag', '<root/>');
 xpath 
-------
 {}
(1 row)

SELECT xpath('root', '<root/>');
   xpath   
-----------
 {<root/>}
(1 row)

-- Round-trip non-ASCII data through xpath().
DO $$
DECLARE
  xml_declaration text := '<?xml version="1.0" encoding="ISO-8859-1"?>';
  degree_symbol text;
  res xml[];
BEGIN
  -- Per the documentation, except when the server encoding is UTF8, xpath()
  -- may not work on non-ASCII data.  The untranslatable_character and
  -- undefined_function traps below, currently dead code, will become relevant
  -- if we remove this limitation.
  IF current_setting('server_encoding') <> 'UTF8' THEN
    RAISE LOG 'skip: encoding % unsupported for xpath',
      current_setting('server_encoding');
    RETURN;
  END IF;

  degree_symbol := convert_from('\xc2b0', 'UTF8');
  res := xpath('text()', (xml_declaration ||
    '<x>' || degree_symbol || '</x>')::xml);
  IF degree_symbol <> res[1]::text THEN
    RAISE 'expected % (%), got % (%)',
      degree_symbol, convert_to(degree_symbol, 'UTF8'),
      res[1], convert_to(res[1]::text, 'UTF8');
  END IF;
EXCEPTION
  -- character with byte sequence 0xc2 0xb0 in encoding "UTF8" has no equivalent in encoding "LATIN8"
  WHEN untranslatable_character
  -- default conversion function for encoding "UTF8" to "MULE_INTERNAL" does not exist
  OR undefined_function
  -- unsupported XML feature
  OR feature_not_supported THEN
    RAISE LOG 'skip: %', SQLERRM;
END
$$;
-- Test xmlexists and xpath_exists
SELECT xmlexists('//town[text() = ''Toronto'']' PASSING BY REF '<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>');
 xmlexists 
-----------
 f
(1 row)

SELECT xmlexists('//town[text() = ''Cwmbran'']' PASSING BY REF '<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>');
 xmlexists 
-----------
 t
(1 row)

SELECT xmlexists('count(/nosuchtag)' PASSING BY REF '<root/>');
 xmlexists 
-----------
 t
(1 row)

SELECT xpath_exists('//town[text() = ''Toronto'']','<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>'::xml);
 xpath_exists 
--------------
 f
(1 row)

SELECT xpath_exists('//town[text() = ''Cwmbran'']','<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>'::xml);
 xpath_exists 
--------------
 t
(1 row)

SELECT xpath_exists('count(/nosuchtag)', '<root/>'::xml);
 xpath_exists 
--------------
 t
(1 row)

INSERT INTO xmltest VALUES (4, '<menu><beers><name>Budvar</name><cost>free</cost><name>Carling</name><cost>lots</cost></beers></menu>'::xml);
INSERT INTO xmltest VALUES (5, '<menu><beers><name>Molson</name><cost>free</cost><name>Carling</name><cost>lots</cost></beers></menu>'::xml);
INSERT INTO xmltest VALUES (6, '<myns:menu xmlns:myns="http://myns.com"><myns:beers><myns:name>Budvar</myns:name><myns:cost>free</myns:cost><myns:name>Carling</myns:name><myns:cost>lots</myns:cost></myns:beers></myns:menu>'::xml);
INSERT INTO xmltest VALUES (7, '<myns:menu xmlns:myns="http://myns.com"><myns:beers><myns:name>Molson</myns:name><myns:cost>free</myns:cost><myns:name>Carling</myns:name><myns:cost>lots</myns:cost></myns:beers></myns:menu>'::xml);
SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beer' PASSING data);
 count 
-------
     0
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beer' PASSING BY REF data BY REF);
 count 
-------
     0
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beers' PASSING BY REF data);
 count 
-------
     2
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beers/name[text() = ''Molson'']' PASSING BY REF data);
 count 
-------
     1
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/menu/beer',data);
 count 
-------
     0
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/menu/beers',data);
 count 
-------
     2
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/menu/beers/name[text() = ''Molson'']',data);
 count 
-------
     1
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/myns:menu/myns:beer',data,ARRAY[ARRAY['myns','http://myns.com']]);
 count 
-------
     0
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/myns:menu/myns:beers',data,ARRAY[ARRAY['myns','http://myns.com']]);
 count 
-------
     2
(1 row)

SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/myns:menu/myns:beers/myns:name[text() = ''Molson'']',data,ARRAY[ARRAY['myns','http://myns.com']]);
 count 
-------
     1
(1 row)

CREATE TABLE query ( expr TEXT );
INSERT INTO query VALUES ('/menu/beers/cost[text() = ''lots'']');
SELECT COUNT(id) FROM xmltest, query WHERE xmlexists(expr PASSING BY REF data);
 count 
-------
     2
(1 row)

-- Test xml_is_well_formed and variants
SELECT xml_is_well_formed_document('<foo>bar</foo>');
 xml_is_well_formed_document 
-----------------------------
 t
(1 row)

SELECT xml_is_well_formed_document('abc');
 xml_is_well_formed_document 
-----------------------------
 f
(1 row)

SELECT xml_is_well_formed_content('<foo>bar</foo>');
 xml_is_well_formed_content 
----------------------------
 t
(1 row)

SELECT xml_is_well_formed_content('abc');
 xml_is_well_formed_content 
----------------------------
 t
(1 row)

SET xmloption TO DOCUMENT;
SELECT xml_is_well_formed('abc');
 xml_is_well_formed 
--------------------
 f
(1 row)

SELECT xml_is_well_formed('<>');
 xml_is_well_formed 
--------------------
 f
(1 row)

SELECT xml_is_well_formed('<abc/>');
 xml_is_well_formed 
--------------------
 t
(1 row)

SELECT xml_is_well_formed('<foo>bar</foo>');
 xml_is_well_formed 
--------------------
 t
(1 row)

SELECT xml_is_well_formed('<foo>bar</foo');
 xml_is_well_formed 
--------------------
 f
(1 row)

SELECT xml_is_well_formed('<foo><bar>baz</foo>');
 xml_is_well_formed 
--------------------
 f
(1 row)

SELECT xml_is_well_formed('<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>');
 xml_is_well_formed 
--------------------
 t
(1 row)

SELECT xml_is_well_formed('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</my:foo>');
 xml_is_well_formed 
--------------------
 f
(1 row)

SELECT xml_is_well_formed('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</pg:foo>');
 xml_is_well_formed 
--------------------
 t
(1 row)

SELECT xml_is_well_formed('<invalidentity>&</abc>');
 xml_is_well_formed 
--------------------
 f
(1 row)

SELECT xml_is_well_formed('<undefinedentity>&idontexist;</abc>');
 xml_is_well_formed 
--------------------
 f
(1 row)

SELECT xml_is_well_formed('<invalidns xmlns=''&lt;''/>');
 xml_is_well_formed 
--------------------
 t
(1 row)

SELECT xml_is_well_formed('<relativens xmlns=''relative''/>');
 xml_is_well_formed 
--------------------
 t
(1 row)

SELECT xml_is_well_formed('<twoerrors>&idontexist;</unbalanced>');
 xml_is_well_formed 
--------------------
 f
(1 row)

SET xmloption TO CONTENT;
SELECT xml_is_well_formed('abc');
 xml_is_well_formed 
--------------------
 t
(1 row)

-- Since xpath() deals with namespaces, it's a bit stricter about
-- what's well-formed and what's not. If we don't obey these rules
-- (i.e. ignore namespace-related errors from libxml), xpath()
-- fails in subtle ways. The following would for example produce
-- the xml value
--   <invalidns xmlns='<'/>
-- which is invalid because '<' may not appear un-escaped in
-- attribute values.
-- Since different libxml versions emit slightly different
-- error messages, we suppress the DETAIL in this test.
\set VERBOSITY terse
SELECT xpath('/*', '<invalidns xmlns=''&lt;''/>');
ERROR:  could not parse XML document
\set VERBOSITY default
-- Again, the XML isn't well-formed for namespace purposes
SELECT xpath('/*', '<nosuchprefix:tag/>');
ERROR:  could not parse XML document
DETAIL:  line 1: Namespace prefix nosuchprefix on tag is not defined
<nosuchprefix:tag/>
                 ^
CONTEXT:  SQL function "xpath" statement 1
-- XPath deprecates relative namespaces, but they're not supposed to
-- throw an error, only a warning.
SELECT xpath('/*', '<relativens xmlns=''relative''/>');
WARNING:  line 1: xmlns: URI relative is not absolute
<relativens xmlns='relative'/>
                            ^
                xpath                 
--------------------------------------
 {"<relativens xmlns=\"relative\"/>"}
(1 row)

-- External entity references should not leak filesystem information.
SELECT XMLPARSE(DOCUMENT '<!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/passwd">]><foo>&c;</foo>');
                            xmlparse                             
-----------------------------------------------------------------
 <!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/passwd">]><foo>&c;</foo>
(1 row)

SELECT XMLPARSE(DOCUMENT '<!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/no.such.file">]><foo>&c;</foo>');
                               xmlparse                                
-----------------------------------------------------------------------
 <!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/no.such.file">]><foo>&c;</foo>
(1 row)

-- This might or might not load the requested DTD, but it mustn't throw error.
SELECT XMLPARSE(DOCUMENT '<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"><chapter>&nbsp;</chapter>');
                                                                       xmlparse                                                                       
------------------------------------------------------------------------------------------------------------------------------------------------------
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"><chapter>&nbsp;</chapter>
(1 row)

-- XMLPATH tests
CREATE TABLE xmldata(data xml);
INSERT INTO xmldata VALUES('<ROWS>
<ROW id="1">
  <COUNTRY_ID>AU</COUNTRY_ID>
  <COUNTRY_NAME>Australia</COUNTRY_NAME>
  <REGION_ID>3</REGION_ID>
</ROW>
<ROW id="2">
  <COUNTRY_ID>CN</COUNTRY_ID>
  <COUNTRY_NAME>China</COUNTRY_NAME>
  <REGION_ID>3</REGION_ID>
</ROW>
<ROW id="3">
  <COUNTRY_ID>HK</COUNTRY_ID>
  <COUNTRY_NAME>HongKong</COUNTRY_NAME>
  <REGION_ID>3</REGION_ID>
</ROW>
<ROW id="4">
  <COUNTRY_ID>IN</COUNTRY_ID>
  <COUNTRY_NAME>India</COUNTRY_NAME>
  <REGION_ID>3</REGION_ID>
</ROW>
<ROW id="5">
  <COUNTRY_ID>JP</COUNTRY_ID>
  <COUNTRY_NAME>Japan</COUNTRY_NAME>
  <REGION_ID>3</REGION_ID><PREMIER_NAME>Sinzo Abe</PREMIER_NAME>
</ROW>
<ROW id="6">
  <COUNTRY_ID>SG</COUNTRY_ID>
  <COUNTRY_NAME>Singapore</COUNTRY_NAME>
  <REGION_ID>3</REGION_ID><SIZE unit="km">791</SIZE>
</ROW>
</ROWS>');
-- XMLTABLE with columns
SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME/text()' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE',
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
 id | _id | country_name | country_id | region_id | size | unit | premier_name  
----+-----+--------------+------------+-----------+------+------+---------------
  1 |   1 | Australia    | AU         |         3 |      |      | not specified
  2 |   2 | China        | CN         |         3 |      |      | not specified
  3 |   3 | HongKong     | HK         |         3 |      |      | not specified
  4 |   4 | India        | IN         |         3 |      |      | not specified
  5 |   5 | Japan        | JP         |         3 |      |      | Sinzo Abe
  6 |   6 | Singapore    | SG         |         3 |  791 | km   | not specified
(6 rows)

CREATE VIEW xmltableview1 AS SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME/text()' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE',
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
SELECT * FROM xmltableview1;
 id | _id | country_name | country_id | region_id | size | unit | premier_name  
----+-----+--------------+------------+-----------+------+------+---------------
  1 |   1 | Australia    | AU         |         3 |      |      | not specified
  2 |   2 | China        | CN         |         3 |      |      | not specified
  3 |   3 | HongKong     | HK         |         3 |      |      | not specified
  4 |   4 | India        | IN         |         3 |      |      | not specified
  5 |   5 | Japan        | JP         |         3 |      |      | Sinzo Abe
  6 |   6 | Singapore    | SG         |         3 |  791 | km   | not specified
(6 rows)

\sv xmltableview1
CREATE OR REPLACE VIEW public.xmltableview1 AS
 SELECT "xmltable".id,
    "xmltable"._id,
    "xmltable".country_name,
    "xmltable".country_id,
    "xmltable".region_id,
    "xmltable".size,
    "xmltable".unit,
    "xmltable".premier_name
   FROM ( SELECT xmldata.data
           FROM xmldata) x,
    LATERAL XMLTABLE(('/ROWS/ROW'::text) PASSING (x.data) COLUMNS id integer PATH ('@id'::text), _id FOR ORDINALITY, country_name text PATH ('COUNTRY_NAME/text()'::text) NOT NULL, country_id text PATH ('COUNTRY_ID'::text), region_id integer PATH ('REGION_ID'::text), size double precision PATH ('SIZE'::text), unit text PATH ('SIZE/@unit'::text), premier_name text DEFAULT ('not specified'::text) PATH ('PREMIER_NAME'::text))
EXPLAIN (COSTS OFF) SELECT * FROM xmltableview1;
               QUERY PLAN                
-----------------------------------------
 Nested Loop
   ->  Seq Scan on xmldata
   ->  Table Function Scan on "xmltable"
(3 rows)

EXPLAIN (COSTS OFF, VERBOSE) SELECT * FROM xmltableview1;
                                                                                                                                                                                                                            QUERY PLAN                                                                                                                                                                                                                            
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Nested Loop
   Output: "xmltable".id, "xmltable"._id, "xmltable".country_name, "xmltable".country_id, "xmltable".region_id, "xmltable".size, "xmltable".unit, "xmltable".premier_name
   ->  Seq Scan on public.xmldata
         Output: xmldata.data
   ->  Table Function Scan on "xmltable"
         Output: "xmltable".id, "xmltable"._id, "xmltable".country_name, "xmltable".country_id, "xmltable".region_id, "xmltable".size, "xmltable".unit, "xmltable".premier_name
         Table Function Call: XMLTABLE(('/ROWS/ROW'::text) PASSING (xmldata.data) COLUMNS id integer PATH ('@id'::text), _id FOR ORDINALITY, country_name text PATH ('COUNTRY_NAME/text()'::text) NOT NULL, country_id text PATH ('COUNTRY_ID'::text), region_id integer PATH ('REGION_ID'::text), size double precision PATH ('SIZE'::text), unit text PATH ('SIZE/@unit'::text), premier_name text DEFAULT ('not specified'::text) PATH ('PREMIER_NAME'::text))
(7 rows)

-- errors
SELECT * FROM XMLTABLE (ROW () PASSING null COLUMNS v1 timestamp) AS f (v1, v2);
ERROR:  XMLTABLE function has 1 columns available but 2 columns specified
-- XMLNAMESPACES tests
SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
                      '/zz:rows/zz:row'
                      PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'
                      COLUMNS a int PATH 'zz:a');
 a  
----
 10
(1 row)

CREATE VIEW xmltableview2 AS SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
                      '/zz:rows/zz:row'
                      PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'
                      COLUMNS a int PATH 'zz:a');
SELECT * FROM xmltableview2;
 a  
----
 10
(1 row)

SELECT * FROM XMLTABLE(XMLNAMESPACES(DEFAULT 'http://x.y'),
                      '/rows/row'
                      PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'
                      COLUMNS a int PATH 'a');
ERROR:  DEFAULT namespace is not supported
SELECT * FROM XMLTABLE('.'
                       PASSING '<foo/>'
                       COLUMNS a text PATH 'foo/namespace::node()');
                  a                   
--------------------------------------
 http://www.w3.org/XML/1998/namespace
(1 row)

-- used in prepare statements
PREPARE pp AS
SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE',
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
EXECUTE pp;
 id | _id | country_name | country_id | region_id | size | unit | premier_name  
----+-----+--------------+------------+-----------+------+------+---------------
  1 |   1 | Australia    | AU         |         3 |      |      | not specified
  2 |   2 | China        | CN         |         3 |      |      | not specified
  3 |   3 | HongKong     | HK         |         3 |      |      | not specified
  4 |   4 | India        | IN         |         3 |      |      | not specified
  5 |   5 | Japan        | JP         |         3 |      |      | Sinzo Abe
  6 |   6 | Singapore    | SG         |         3 |  791 | km   | not specified
(6 rows)

SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS "COUNTRY_NAME" text, "REGION_ID" int);
 COUNTRY_NAME | REGION_ID 
--------------+-----------
 India        |         3
 Japan        |         3
(2 rows)

SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS id FOR ORDINALITY, "COUNTRY_NAME" text, "REGION_ID" int);
 id | COUNTRY_NAME | REGION_ID 
----+--------------+-----------
  1 | India        |         3
  2 | Japan        |         3
(2 rows)

SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS id int PATH '@id', "COUNTRY_NAME" text, "REGION_ID" int);
 id | COUNTRY_NAME | REGION_ID 
----+--------------+-----------
  4 | India        |         3
  5 | Japan        |         3
(2 rows)

SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS id int PATH '@id');
 id 
----
  4
  5
(2 rows)

SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS id FOR ORDINALITY);
 id 
----
  1
  2
(2 rows)

SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS id int PATH '@id', "COUNTRY_NAME" text, "REGION_ID" int, rawdata xml PATH '.');
 id | COUNTRY_NAME | REGION_ID |                             rawdata                              
----+--------------+-----------+------------------------------------------------------------------
  4 | India        |         3 | <ROW id="4">                                                    +
    |              |           |   <COUNTRY_ID>IN</COUNTRY_ID>                                   +
    |              |           |   <COUNTRY_NAME>India</COUNTRY_NAME>                            +
    |              |           |   <REGION_ID>3</REGION_ID>                                      +
    |              |           | </ROW>
  5 | Japan        |         3 | <ROW id="5">                                                    +
    |              |           |   <COUNTRY_ID>JP</COUNTRY_ID>                                   +
    |              |           |   <COUNTRY_NAME>Japan</COUNTRY_NAME>                            +
    |              |           |   <REGION_ID>3</REGION_ID><PREMIER_NAME>Sinzo Abe</PREMIER_NAME>+
    |              |           | </ROW>
(2 rows)

SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS id int PATH '@id', "COUNTRY_NAME" text, "REGION_ID" int, rawdata xml PATH './*');
 id | COUNTRY_NAME | REGION_ID |                                                           rawdata                                                           
----+--------------+-----------+-----------------------------------------------------------------------------------------------------------------------------
  4 | India        |         3 | <COUNTRY_ID>IN</COUNTRY_ID><COUNTRY_NAME>India</COUNTRY_NAME><REGION_ID>3</REGION_ID>
  5 | Japan        |         3 | <COUNTRY_ID>JP</COUNTRY_ID><COUNTRY_NAME>Japan</COUNTRY_NAME><REGION_ID>3</REGION_ID><PREMIER_NAME>Sinzo Abe</PREMIER_NAME>
(2 rows)

SELECT * FROM xmltable('/root' passing '<root><element>a1a<!-- aaaa -->a2a<?aaaaa?> <!--z-->  bbbb<x>xxx</x>cccc</element></root>' COLUMNS element text);
       element        
----------------------
 a1aa2a   bbbbxxxcccc
(1 row)

SELECT * FROM xmltable('/root' passing '<root><element>a1a<!-- aaaa -->a2a<?aaaaa?> <!--z-->  bbbb<x>xxx</x>cccc</element></root>' COLUMNS element text PATH 'element/text()'); -- should fail
ERROR:  more than one value returned by column XPath expression
-- CDATA test
select * from xmltable('d/r' passing '<d><r><c><![CDATA[<hello> &"<>!<a>foo</a>]]></c></r><r><c>2</c></r></d>' columns c text);
            c            
-------------------------
 <hello> &"<>!<a>foo</a>
 2
(2 rows)

-- XML builtin entities
SELECT * FROM xmltable('/x/a' PASSING '<x><a><ent>&apos;</ent></a><a><ent>&quot;</ent></a><a><ent>&amp;</ent></a><a><ent>&lt;</ent></a><a><ent>&gt;</ent></a></x>' COLUMNS ent text);
 ent 
-----
 '
 "
 &
 <
 >
(5 rows)

SELECT * FROM xmltable('/x/a' PASSING '<x><a><ent>&apos;</ent></a><a><ent>&quot;</ent></a><a><ent>&amp;</ent></a><a><ent>&lt;</ent></a><a><ent>&gt;</ent></a></x>' COLUMNS ent xml);
       ent        
------------------
 <ent>'</ent>
 <ent>"</ent>
 <ent>&amp;</ent>
 <ent>&lt;</ent>
 <ent>&gt;</ent>
(5 rows)

EXPLAIN (VERBOSE, COSTS OFF)
SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE',
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
                                                                                                                                                                                                                        QUERY PLAN                                                                                                                                                                                                                         
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Nested Loop
   Output: "xmltable".id, "xmltable"._id, "xmltable".country_name, "xmltable".country_id, "xmltable".region_id, "xmltable".size, "xmltable".unit, "xmltable".premier_name
   ->  Seq Scan on public.xmldata
         Output: xmldata.data
   ->  Table Function Scan on "xmltable"
         Output: "xmltable".id, "xmltable"._id, "xmltable".country_name, "xmltable".country_id, "xmltable".region_id, "xmltable".size, "xmltable".unit, "xmltable".premier_name
         Table Function Call: XMLTABLE(('/ROWS/ROW'::text) PASSING (xmldata.data) COLUMNS id integer PATH ('@id'::text), _id FOR ORDINALITY, country_name text PATH ('COUNTRY_NAME'::text) NOT NULL, country_id text PATH ('COUNTRY_ID'::text), region_id integer PATH ('REGION_ID'::text), size double precision PATH ('SIZE'::text), unit text PATH ('SIZE/@unit'::text), premier_name text DEFAULT ('not specified'::text) PATH ('PREMIER_NAME'::text))
(7 rows)

-- test qual
SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS "COUNTRY_NAME" text, "REGION_ID" int) WHERE "COUNTRY_NAME" = 'Japan';
 COUNTRY_NAME | REGION_ID 
--------------+-----------
 Japan        |         3
(1 row)

EXPLAIN (VERBOSE, COSTS OFF)
SELECT xmltable.* FROM xmldata, LATERAL xmltable('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]' PASSING data COLUMNS "COUNTRY_NAME" text, "REGION_ID" int) WHERE "COUNTRY_NAME" = 'Japan';
                                                                                    QUERY PLAN                                                                                    
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Nested Loop
   Output: "xmltable"."COUNTRY_NAME", "xmltable"."REGION_ID"
   ->  Seq Scan on public.xmldata
         Output: xmldata.data
   ->  Table Function Scan on "xmltable"
         Output: "xmltable"."COUNTRY_NAME", "xmltable"."REGION_ID"
         Table Function Call: XMLTABLE(('/ROWS/ROW[COUNTRY_NAME="Japan" or COUNTRY_NAME="India"]'::text) PASSING (xmldata.data) COLUMNS "COUNTRY_NAME" text, "REGION_ID" integer)
         Filter: ("xmltable"."COUNTRY_NAME" = 'Japan'::text)
(8 rows)

-- should to work with more data
INSERT INTO xmldata VALUES('<ROWS>
<ROW id="10">
  <COUNTRY_ID>CZ</COUNTRY_ID>
  <COUNTRY_NAME>Czech Republic</COUNTRY_NAME>
  <REGION_ID>2</REGION_ID><PREMIER_NAME>Milos Zeman</PREMIER_NAME>
</ROW>
<ROW id="11">
  <COUNTRY_ID>DE</COUNTRY_ID>
  <COUNTRY_NAME>Germany</COUNTRY_NAME>
  <REGION_ID>2</REGION_ID>
</ROW>
<ROW id="12">
  <COUNTRY_ID>FR</COUNTRY_ID>
  <COUNTRY_NAME>France</COUNTRY_NAME>
  <REGION_ID>2</REGION_ID>
</ROW>
</ROWS>');
INSERT INTO xmldata VALUES('<ROWS>
<ROW id="20">
  <COUNTRY_ID>EG</COUNTRY_ID>
  <COUNTRY_NAME>Egypt</COUNTRY_NAME>
  <REGION_ID>1</REGION_ID>
</ROW>
<ROW id="21">
  <COUNTRY_ID>SD</COUNTRY_ID>
  <COUNTRY_NAME>Sudan</COUNTRY_NAME>
  <REGION_ID>1</REGION_ID>
</ROW>
</ROWS>');
SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE',
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
 id | _id |  country_name  | country_id | region_id | size | unit | premier_name  
----+-----+----------------+------------+-----------+------+------+---------------
  1 |   1 | Australia      | AU         |         3 |      |      | not specified
  2 |   2 | China          | CN         |         3 |      |      | not specified
  3 |   3 | HongKong       | HK         |         3 |      |      | not specified
  4 |   4 | India          | IN         |         3 |      |      | not specified
  5 |   5 | Japan          | JP         |         3 |      |      | Sinzo Abe
  6 |   6 | Singapore      | SG         |         3 |  791 | km   | not specified
 10 |   1 | Czech Republic | CZ         |         2 |      |      | Milos Zeman
 11 |   2 | Germany        | DE         |         2 |      |      | not specified
 12 |   3 | France         | FR         |         2 |      |      | not specified
 20 |   1 | Egypt          | EG         |         1 |      |      | not specified
 21 |   2 | Sudan          | SD         |         1 |      |      | not specified
(11 rows)

SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE',
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified')
  WHERE region_id = 2;
 id | _id |  country_name  | country_id | region_id | size | unit | premier_name  
----+-----+----------------+------------+-----------+------+------+---------------
 10 |   1 | Czech Republic | CZ         |         2 |      |      | Milos Zeman
 11 |   2 | Germany        | DE         |         2 |      |      | not specified
 12 |   3 | France         | FR         |         2 |      |      | not specified
(3 rows)

EXPLAIN (VERBOSE, COSTS OFF)
SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE',
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified')
  WHERE region_id = 2;
                                                                                                                                                                                                                        QUERY PLAN                                                                                                                                                                                                                         
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Nested Loop
   Output: "xmltable".id, "xmltable"._id, "xmltable".country_name, "xmltable".country_id, "xmltable".region_id, "xmltable".size, "xmltable".unit, "xmltable".premier_name
   ->  Seq Scan on public.xmldata
         Output: xmldata.data
   ->  Table Function Scan on "xmltable"
         Output: "xmltable".id, "xmltable"._id, "xmltable".country_name, "xmltable".country_id, "xmltable".region_id, "xmltable".size, "xmltable".unit, "xmltable".premier_name
         Table Function Call: XMLTABLE(('/ROWS/ROW'::text) PASSING (xmldata.data) COLUMNS id integer PATH ('@id'::text), _id FOR ORDINALITY, country_name text PATH ('COUNTRY_NAME'::text) NOT NULL, country_id text PATH ('COUNTRY_ID'::text), region_id integer PATH ('REGION_ID'::text), size double precision PATH ('SIZE'::text), unit text PATH ('SIZE/@unit'::text), premier_name text DEFAULT ('not specified'::text) PATH ('PREMIER_NAME'::text))
         Filter: ("xmltable".region_id = 2)
(8 rows)

-- should fail, NULL value
SELECT  xmltable.*
   FROM (SELECT data FROM xmldata) x,
        LATERAL XMLTABLE('/ROWS/ROW'
                         PASSING data
                         COLUMNS id int PATH '@id',
                                  _id FOR ORDINALITY,
                                  country_name text PATH 'COUNTRY_NAME' NOT NULL,
                                  country_id text PATH 'COUNTRY_ID',
                                  region_id int PATH 'REGION_ID',
                                  size float PATH 'SIZE' NOT NULL,
                                  unit text PATH 'SIZE/@unit',
                                  premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
ERROR:  null is not allowed in column "size"
-- if all is ok, then result is empty
-- one line xml test
WITH
   x AS (SELECT proname, proowner, procost::numeric, pronargs,
                array_to_string(proargnames,',') as proargnames,
                case when proargtypes <> '' then array_to_string(proargtypes::oid[],',') end as proargtypes
           FROM pg_proc WHERE proname = 'f_leak'),
   y AS (SELECT xmlelement(name proc,
                           xmlforest(proname, proowner,
                                     procost, pronargs,
                                     proargnames, proargtypes)) as proc
           FROM x),
   z AS (SELECT xmltable.*
           FROM y,
                LATERAL xmltable('/proc' PASSING proc
                                 COLUMNS proname name,
                                         proowner oid,
                                         procost float,
                                         pronargs int,
                                         proargnames text,
                                         proargtypes text))
   SELECT * FROM z
   EXCEPT SELECT * FROM x;
 proname | proowner | procost | pronargs | proargnames | proargtypes 
---------+----------+---------+----------+-------------+-------------
(0 rows)

-- multi line xml test, result should be empty too
WITH
   x AS (SELECT proname, proowner, procost::numeric, pronargs,
                array_to_string(proargnames,',') as proargnames,
                case when proargtypes <> '' then array_to_string(proargtypes::oid[],',') end as proargtypes
           FROM pg_proc),
   y AS (SELECT xmlelement(name data,
                           xmlagg(xmlelement(name proc,
                                             xmlforest(proname, proowner, procost,
                                                       pronargs, proargnames, proargtypes)))) as doc
           FROM x),
   z AS (SELECT xmltable.*
           FROM y,
                LATERAL xmltable('/data/proc' PASSING doc
                                 COLUMNS proname name,
                                         proowner oid,
                                         procost float,
                                         pronargs int,
                                         proargnames text,
                                         proargtypes text))
   SELECT * FROM z
   EXCEPT SELECT * FROM x;
 proname | proowner | procost | pronargs | proargnames | proargtypes 
---------+----------+---------+----------+-------------+-------------
(0 rows)

CREATE TABLE xmltest2(x xml, _path text);
INSERT INTO xmltest2 VALUES('<d><r><ac>1</ac></r></d>', 'A');
INSERT INTO xmltest2 VALUES('<d><r><bc>2</bc></r></d>', 'B');
INSERT INTO xmltest2 VALUES('<d><r><cc>3</cc></r></d>', 'C');
INSERT INTO xmltest2 VALUES('<d><r><dc>2</dc></r></d>', 'D');
SELECT xmltable.* FROM xmltest2, LATERAL xmltable('/d/r' PASSING x COLUMNS a int PATH '' || lower(_path) || 'c');
 a 
---
 1
 2
 3
 2
(4 rows)

SELECT xmltable.* FROM xmltest2, LATERAL xmltable(('/d/r/' || lower(_path) || 'c') PASSING x COLUMNS a int PATH '.');
 a 
---
 1
 2
 3
 2
(4 rows)

SELECT xmltable.* FROM xmltest2, LATERAL xmltable(('/d/r/' || lower(_path) || 'c') PASSING x COLUMNS a int PATH 'x' DEFAULT ascii(_path) - 54);
 a  
----
 11
 12
 13
 14
(4 rows)

-- XPath result can be boolean or number too
SELECT * FROM XMLTABLE('*' PASSING '<a>a</a>' COLUMNS a xml PATH '.', b text PATH '.', c text PATH '"hi"', d boolean PATH '. = "a"', e integer PATH 'string-length(.)');
    a     | b | c  | d | e 
----------+---+----+---+---
 <a>a</a> | a | hi | t | 1
(1 row)

\x
SELECT * FROM XMLTABLE('*' PASSING '<e>pre<!--c1--><?pi arg?><![CDATA[&ent1]]><n2>&amp;deep</n2>post</e>' COLUMNS x xml PATH 'node()', y xml PATH '/');
-[ RECORD 1 ]-----------------------------------------------------------
x | pre<!--c1--><?pi arg?><![CDATA[&ent1]]><n2>&amp;deep</n2>post
y | <e>pre<!--c1--><?pi arg?><![CDATA[&ent1]]><n2>&amp;deep</n2>post</e>+
  | 

\x
SELECT * FROM XMLTABLE('.' PASSING XMLELEMENT(NAME a) columns a varchar(20) PATH '"<foo/>"', b xml PATH '"<foo/>"');
   a    |      b       
--------+--------------
 <foo/> | &lt;foo/&gt;
(1 row)