From 7c0379516f367cf6a3709c46b2fed12777468130 Mon Sep 17 00:00:00 2001
From: Dean Rasheed <dean.a.rasheed@gmail.com>
Date: Sun, 12 Jan 2025 12:59:40 +0000
Subject: [PATCH] Fix XMLTABLE() deparsing to quote namespace names if
 necessary.

When deparsing an XMLTABLE() expression, XML namespace names were not
quoted. However, since they are parsed as ColLabel tokens, some names
require double quotes to ensure that they are properly interpreted.
Fix by using quote_identifier() in the deparsing code.

Back-patch to all supported versions.

Dean Rasheed, reviewed by Tom Lane.

Discussion: https://postgr.es/m/CAEZATCXTpAS%3DncfLNTZ7YS6O5puHeLg_SUYAit%2Bcs7wsrd9Msg%40mail.gmail.com
---
 src/backend/utils/adt/ruleutils.c   |  3 ++-
 src/test/regress/expected/xml.out   | 10 +++++++---
 src/test/regress/expected/xml_1.out |  8 +++++---
 src/test/regress/expected/xml_2.out | 10 +++++++---
 src/test/regress/sql/xml.sql        |  8 +++++---
 5 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index bc1fbe97a63..035faf418f0 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -10923,7 +10923,8 @@ get_tablefunc(TableFunc *tf, deparse_context *context, bool showimplicit)
 			if (ns_node != NULL)
 			{
 				get_rule_expr(expr, context, showimplicit);
-				appendStringInfo(buf, " AS %s", strVal(ns_node));
+				appendStringInfo(buf, " AS %s",
+								 quote_identifier(strVal(ns_node)));
 			}
 			else
 			{
diff --git a/src/test/regress/expected/xml.out b/src/test/regress/expected/xml.out
index 5b6ae62c044..f9b7ec0bab8 100644
--- a/src/test/regress/expected/xml.out
+++ b/src/test/regress/expected/xml.out
@@ -1149,16 +1149,20 @@ SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
  10
 (1 row)
 
-CREATE VIEW xmltableview2 AS SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
-                      '/zz:rows/zz: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');
+                      COLUMNS a int PATH 'Zz:a');
 SELECT * FROM xmltableview2;
  a  
 ----
  10
 (1 row)
 
+\sv xmltableview2
+CREATE OR REPLACE VIEW public.xmltableview2 AS
+ SELECT "xmltable".a
+   FROM XMLTABLE(XMLNAMESPACES ('http://x.y'::text AS "Zz"), ('/Zz:rows/Zz:row'::text) PASSING ('<rows xmlns="http://x.y"><row><a>10</a></row></rows>'::xml) COLUMNS a integer PATH ('Zz:a'::text))
 SELECT * FROM XMLTABLE(XMLNAMESPACES(DEFAULT 'http://x.y'),
                       '/rows/row'
                       PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'
diff --git a/src/test/regress/expected/xml_1.out b/src/test/regress/expected/xml_1.out
index 3477606af76..5b28ea01eea 100644
--- a/src/test/regress/expected/xml_1.out
+++ b/src/test/regress/expected/xml_1.out
@@ -885,10 +885,10 @@ ERROR:  unsupported XML feature
 LINE 3:                       PASSING '<rows xmlns="http://x.y"><row...
                                       ^
 DETAIL:  This functionality requires the server to be built with libxml support.
-CREATE VIEW xmltableview2 AS SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
-                      '/zz:rows/zz: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');
+                      COLUMNS a int PATH 'Zz:a');
 ERROR:  unsupported XML feature
 LINE 3:                       PASSING '<rows xmlns="http://x.y"><row...
                                       ^
@@ -897,6 +897,8 @@ SELECT * FROM xmltableview2;
 ERROR:  relation "xmltableview2" does not exist
 LINE 1: SELECT * FROM xmltableview2;
                       ^
+\sv xmltableview2
+ERROR:  relation "xmltableview2" does not exist
 SELECT * FROM XMLTABLE(XMLNAMESPACES(DEFAULT 'http://x.y'),
                       '/rows/row'
                       PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'
diff --git a/src/test/regress/expected/xml_2.out b/src/test/regress/expected/xml_2.out
index 6638458ba2d..044a4917d86 100644
--- a/src/test/regress/expected/xml_2.out
+++ b/src/test/regress/expected/xml_2.out
@@ -1135,16 +1135,20 @@ SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
  10
 (1 row)
 
-CREATE VIEW xmltableview2 AS SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
-                      '/zz:rows/zz: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');
+                      COLUMNS a int PATH 'Zz:a');
 SELECT * FROM xmltableview2;
  a  
 ----
  10
 (1 row)
 
+\sv xmltableview2
+CREATE OR REPLACE VIEW public.xmltableview2 AS
+ SELECT "xmltable".a
+   FROM XMLTABLE(XMLNAMESPACES ('http://x.y'::text AS "Zz"), ('/Zz:rows/Zz:row'::text) PASSING ('<rows xmlns="http://x.y"><row><a>10</a></row></rows>'::xml) COLUMNS a integer PATH ('Zz:a'::text))
 SELECT * FROM XMLTABLE(XMLNAMESPACES(DEFAULT 'http://x.y'),
                       '/rows/row'
                       PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'
diff --git a/src/test/regress/sql/xml.sql b/src/test/regress/sql/xml.sql
index e3f90db4d56..e908b6c3957 100644
--- a/src/test/regress/sql/xml.sql
+++ b/src/test/regress/sql/xml.sql
@@ -393,13 +393,15 @@ SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
                       PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'
                       COLUMNS a int PATH 'zz:a');
 
-CREATE VIEW xmltableview2 AS SELECT * FROM XMLTABLE(XMLNAMESPACES('http://x.y' AS zz),
-                      '/zz:rows/zz: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');
+                      COLUMNS a int PATH 'Zz:a');
 
 SELECT * FROM xmltableview2;
 
+\sv xmltableview2
+
 SELECT * FROM XMLTABLE(XMLNAMESPACES(DEFAULT 'http://x.y'),
                       '/rows/row'
                       PASSING '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'