From fca715a250a9a49d23193b34a72b04e80e024d71 Mon Sep 17 00:00:00 2001 From: Markus Winand Date: Tue, 27 Mar 2018 08:47:53 +0000 Subject: [PATCH 1/2] Accept TEXT and CDATA nodes in XMLTABLE's column_expression. Column_expressions that match TEXT or CDATA nodes must return the contents of the node itself, not the content of the non-existing childs (i.e. the empty string). --- src/backend/utils/adt/xml.c | 14 +++++++++----- src/test/regress/expected/xml_2.out | 12 ++++++------ src/test/regress/sql/xml.sql | 4 ++-- 3 files changed, 17 insertions(+), 13 deletions(-) diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c index 7cdb87e..3e8cc55 100644 --- a/src/backend/utils/adt/xml.c +++ b/src/backend/utils/adt/xml.c @@ -4509,8 +4509,15 @@ XmlTableGetValue(TableFuncScanState *state, int colnum, { xmlChar *str; + /* Most nodes (elements and even attributes) store their data in child nodes. + * If they don't have child nodes, it means that they are empty (e.g. ). + * Text nodes and CDATA sections are the exception: the don't have childs + * but have content in the Text/CDATA node itself. + */ str = xmlNodeListGetString(xtCxt->doc, - xpathobj->nodesetval->nodeTab[0]->xmlChildrenNode, + xpathobj->nodesetval->nodeTab[0]->type == XML_CDATA_SECTION_NODE || + xpathobj->nodesetval->nodeTab[0]->type == XML_TEXT_NODE ? xpathobj->nodesetval->nodeTab[0] + : xpathobj->nodesetval->nodeTab[0]->xmlChildrenNode, 1); if (str != NULL) @@ -4531,10 +4538,7 @@ XmlTableGetValue(TableFuncScanState *state, int colnum, { /* * This line ensure mapping of empty tags to PostgreSQL - * value. Usually we would to map a empty tag to empty - * string. But this mapping can create empty string when - * user doesn't expect it - when empty tag is enforced by - * libxml2 - when user uses a text() function for example. + * values. */ cstr = ""; } diff --git a/src/test/regress/expected/xml_2.out b/src/test/regress/expected/xml_2.out index 112ebe4..cb865a9 100644 --- a/src/test/regress/expected/xml_2.out +++ b/src/test/regress/expected/xml_2.out @@ -1004,7 +1004,7 @@ SELECT xmltable.* PASSING data COLUMNS id int PATH '@id', _id FOR ORDINALITY, - country_name text PATH 'COUNTRY_NAME' NOT NULL, + 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', @@ -1026,7 +1026,7 @@ CREATE VIEW xmltableview1 AS SELECT xmltable.* PASSING data COLUMNS id int PATH '@id', _id FOR ORDINALITY, - country_name text PATH 'COUNTRY_NAME' NOT NULL, + 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', @@ -1055,7 +1055,7 @@ CREATE OR REPLACE VIEW public.xmltableview1 AS "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) 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)) + 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 ----------------------------------------- @@ -1065,15 +1065,15 @@ EXPLAIN (COSTS OFF) SELECT * FROM xmltableview1; (3 rows) EXPLAIN (COSTS OFF, VERBOSE) SELECT * FROM xmltableview1; - QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ + 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)) + 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) -- XMLNAMESPACES tests diff --git a/src/test/regress/sql/xml.sql b/src/test/regress/sql/xml.sql index cb96e18..c223603 100644 --- a/src/test/regress/sql/xml.sql +++ b/src/test/regress/sql/xml.sql @@ -349,7 +349,7 @@ SELECT xmltable.* PASSING data COLUMNS id int PATH '@id', _id FOR ORDINALITY, - country_name text PATH 'COUNTRY_NAME' NOT NULL, + 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', @@ -362,7 +362,7 @@ CREATE VIEW xmltableview1 AS SELECT xmltable.* PASSING data COLUMNS id int PATH '@id', _id FOR ORDINALITY, - country_name text PATH 'COUNTRY_NAME' NOT NULL, + 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', -- 1.9.1