Thread: [HACKERS] proposal - Default namespaces for XPath expressions (PostgreSQL 11)

Hello, this patch have been ignored for a long time since its proposal...

At Sat, 11 Mar 2017 20:44:31 +0100, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRB+WDyDcZyGmfRdJ0HOoXugeaL-KNFeK9YA5Z10JN9qfA@mail.gmail.com>
> Hi
> 
> This proposal is followup of implementation of XMLTABLE.
> 
> Lot of XML documents has assigned document namespace.
> 
> <rows xmlns="http://x.y"><row><a>10</a></row></rows>
> 
> For these XML document any search path must use schema "http://x.y". This
> is not too intuitive, and from XMLTABLE usage is not too user friendly,
> because the default column path (same like column name) cannot be used. A
> solution of this issue is default namespace - defined in SQL/XML.
> 
> example - related to previous xml
> 
> without default namespace:
> XMLTABLE(NAMESPACES('http://x.y' AS aux),
>                     '/aux:rows/aux:row' PASSING ...
>                     COLUMNS a int PATH 'aux:a')
> 
> with default namespace
> XMLTABLE(NAMESPACES(DEFAULT 'http://x.y'),
>                     '/rows/row' PASSING ...
>                     COLUMNS a int);
> 
> 
> Unfortunately the libxml2 doesn't support default namespaces in XPath
> expressions. Because the libxml2 functionality is frozen, there is not big
> chance for support in near future. A implementation is not too hard -
> although it requires simple XPath expressions state translator.
> 
> The databases with XMLTABLE implementation supports default namespace for
> XPath expressions.
> 
> The patch for initial implementation is attached.

The original message is a bit less informative for those who
wants to review this but are not accustomed (like me) to this
area. I try to augment this with a bit more information. (Perhaps)

An example of this issue can be as follows.

create table t1 (id int, doc xml);
insert into t1  values (1, '<rows xmlns="http://x.y"><row><a>10</a></row></rows>'), (2, '<rows
xmlns="http://x.y"><row><a>20</a></row></rows>'),(3, '<rows xmlns="http://x.y"><row><a>30</a></row></rows>'), (4,
'<rowsxmlns="http://x.y"><row><a>40</a></row></rows>');
 
select x.* from t1, xmltable('/rows/row' passing t1.doc columns data int PATH 'a') as x;
|  data 
| ------
| (0 rows)
select x.* from t1, xmltable(XMLNAMESPACES('http://x.y' as n), '/n:rows/n:row' passing t1.doc columns data int PATH
'n:a')as x;
 
|  data 
| ------
|    10
|    20
|    30
|    40
| (4 rows)

But, currently the follwing command fails with error.

select x.* from t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'), '/rows/row' passing t1.doc columns data int PATH 'a')
asx;
 
| ERROR:  DEFAULT namespace is not supported

This patch let PostgreSQL allow this syntax by transforming xpath
string when DEFAULT namespace is defined.

=======================
I have some review comments.

This patch still applies with shifts and works as expected.

1. Uniformity among simliar features
 As mentioned in the proposal, but it is lack of uniformity that the xpath transformer is applied only to xmltable and
notfor other xpath related functions.
 


2. XML comformance
  I'm not yet sure this works for the all extent of the  available syntax but at least fails for the following
expression.

(delete from t1;)
insert into t1   values  (5, '<rows xmlns="http://x.y"><row><a hoge="haha">50</a></row></rows>');

select x.* from t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'), '/rows/row' passing t1.doc columns data int PATH
'a[1][@hoge]')as x;
 
>  data 
> ------
>      
> (1 row)

 The following expression works.

select x.* from t1, xmltable(XMLNAMESPACES('http://x.y' as x), '/x:rows/x:row' passing t1.doc columns data int PATH
'x:a[1][@hoge]')as x;
 
>  data 
> ------
>    50
> (1 row)
 The w3c says as follows.
 https://www.w3.org/TR/xml-names/#defaulting > The namespace name for an unprefixed attribute name always has no value.

 
 We currently don't have a means to make sure that this works correctly for the whole extent. More regression test
helps?
 

3. The predefined prefix for default namespace
 The patch defines the name of the defaut namespace as "pgdefnamespace". If a default namespace is defined, a namespace
ismade with the name and with_default_ns is true. If a namespace with the name is defined, a namespace is made also
withthe same name but with_default_ns is false. This causes a confused behavior.
 

select x.* from t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.x', 'http://x.y' as pgdefnamespace), '/rows/row' passing
t1.doccolumns data int PATH 'a') as x;
 
|  data 
| ------
|    10
|    20
|    30
|    40
| (4 rows)
The reason for the design is the fact that xmlXPathRegisterNsdoesn't accept NULL or empty string as a namespace prefix
anditonly accepts a string consists of valid XML caharacters.
 
Even if we are to live with such restriction and such name ishardly used, a namespace prefix with the name should
berejected.


4. A mistake in the documentaion ?
The documentaion says about the XMLNAMESPACES clause as thefolows.

https://www.postgresql.org/docs/10/static/functions-xml.html
> The optional XMLNAMESPACES clause is a comma-separated list of
> namespaces. It specifies the XML namespaces used in the document
> and their aliases.

As far as looking into XmlTableSetNamespace, (and if I read the
documentation correctly) the defined namespaces are not applied
on documents, but expressions. This patch is not to blame for
this. So this will be another patch backbatchable to Pg10.

| The optional XMLNAMESPACES clause is a comma-separated list of
| namespaces. It specifies the XML namespaces used in the
| row_expression.



regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center



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Hi, thanks for the new patch.

# The patch is missing xpath_parser.h. That of the first patch was usable.

At Thu, 28 Sep 2017 07:59:41 +0200, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRBMQa07a=+qQAVMtz5M_hqkJBhiQSOP76+-BrFDj37pvg@mail.gmail.com>
> Hi
> 
> now xpath and xpath_exists supports default namespace too

At Wed, 27 Sep 2017 22:41:52 +0200, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRCZ8oneG7g2vxs9ux71n8A9twwUO7zQpJiuz+7RGSpSuw@mail.gmail.com>
> > 1. Uniformity among simliar features
> >
> >   As mentioned in the proposal, but it is lack of uniformity that
> >   the xpath transformer is applied only to xmltable and not for
> >   other xpath related functions.
> >
> 
> I have to fix the XPath function. The SQL/XML function Xmlexists doesn't
> support namespaces/

Sorry, I forgot to care about that. (And the definition of
namespace array is of course fabricated by me). I'd like to leave
this to committers.  Anyway it is working but the syntax (or
whether it is acceptable) is still arguable.

SELECT xpath('/a/text()', '<my:a xmlns:my="http://example.com">test</my:a>',            ARRAY[ARRAY['',
'http://example.com']]);
|  xpath  
| --------
|  {test}
| (1 row)


The internal name is properly rejected, but the current internal
name (pgdefnamespace.pgsqlxml.internal) seems a bit too long. We
are preserving some short names and reject them as
user-defined. Doesn't just 'pgsqlxml' work?


Default namespace correctly become to be applied on bare
attribute names.

> updated doc,
> fixed all variants of expected result test file

Sorry for one by one comment but I found another misbehavior.

create table t1 (id int, doc xml);
insert into t1   values  (5, '<rows xmlns="http://x.y"><row><a hoge="haha">50</a></row></rows>');
select x.* from t1, xmltable(XMLNAMESPACES('http://x.y' AS x), '/x:rows/x:row' passing t1.doc columns data int PATH
'child::x:a[1][attribute::hoge="haha"]')as x;
 
|  data 
| ------
|    50

but the following fails.

select x.* from t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'), '/rows/row' passing t1.doc columns data int PATH
'child::a[1][attribute::hoge="haha"]')as x;
 
|  data 
| ------
|      
| (1 row)

Perhaps child::a is not prefixed by the transformation.

XPath might be complex enough so that it's worth switching to
yacc/lex based transformer that is formally verifiable and won't
need a bunch of cryptic tests that finally cannot prove the
completeness. synchronous_standy_names is far simpler than XPath
but using yacc/lex parser.


Anyway the following is nitpicking of the current xpath_parser.c.

- NODENAME_FIRSTCHAR allows '-' as the first char but it is excluded from NameStartChar
(https://www.w3.org/TR/REC-xml/#NT-NameStartChar)I think characters with high-bit set is okay. Also IS_NODENAME_CHAR
shouldbe changed.
 

- NODENAME_FIRSTCHAR and IS_NODENAME_CHAR is in the same category but have different naming schemes. Can these are
namedin the same way?
 

- The current transoformer seems to using up to one token stack depth. Maybe the stack is needless. (pushed token is
alwayspopped just after)
 

regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center



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At Mon, 2 Oct 2017 12:43:19 +0200, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRCD8=AzbRJQ2_2rp3+uzade9GHbm0DAF3-t__yVtzo2cA@mail.gmail.com>
> > Sorry, I forgot to care about that. (And the definition of
> > namespace array is of course fabricated by me). I'd like to leave
> > this to committers.  Anyway it is working but the syntax (or
> > whether it is acceptable) is still arguable.
> >
> > SELECT xpath('/a/text()', '<my:a xmlns:my="http://example.com">
> > test</my:a>',
> >              ARRAY[ARRAY['', 'http://example.com']]);
> > |  xpath
> > | --------
> > |  {test}
> > | (1 row)
> >
> >
> > The internal name is properly rejected, but the current internal
> > name (pgdefnamespace.pgsqlxml.internal) seems a bit too long. We
> > are preserving some short names and reject them as
> > user-defined. Doesn't just 'pgsqlxml' work?
> >
> 
> LibXML2 does trim to 100 bytes length names. So
> pgdefnamespace.pgsqlxml.internal
> is safe from this perspective.
> 
> I would to decraese a risk of possible collision, so longer string is
> better. Maybe "pgsqlxml.internal" is good enoug - I have not a idea. But if
> somewhere will be this string printed, then
> "pgdefnamespace.pgsqlxml.internal" has clean semantic, and it is reason,
> why I prefer this string. PostgreSQL uses 63 bytes names - and this string
> is correct too.

Ok, I'm fine with that.

> > Default namespace correctly become to be applied on bare
> > attribute names.
> >
> > > updated doc,
> > > fixed all variants of expected result test file
> >
> > Sorry for one by one comment but I found another misbehavior.
> >
> > create table t1 (id int, doc xml);
> > insert into t1
> >    values
> >    (5, '<rows xmlns="http://x.y"><row><a hoge="haha">50</a></row></
> > rows>');
> > select x.* from t1, xmltable(XMLNAMESPACES('http://x.y' AS x),
> > '/x:rows/x:row' passing t1.doc columns data int PATH
> > 'child::x:a[1][attribute::hoge="haha"]') as x;
> > |  data
> > | ------
> > |    50
> >
> > but the following fails.
> >
> > select x.* from t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'),
> > '/rows/row' passing t1.doc columns data int PATH
> > 'child::a[1][attribute::hoge="haha"]') as x;
> > |  data
> > | ------
> > |
> > | (1 row)
> >
> > Perhaps child::a is not prefixed by the transformation.
> >
> > XPath might be complex enough so that it's worth switching to
> > yacc/lex based transformer that is formally verifiable and won't
> > need a bunch of cryptic tests that finally cannot prove the
> > completeness. synchronous_standy_names is far simpler than XPath
> > but using yacc/lex parser.
> >
> 
> I don't think (not yet) - it is simple state machine now, and when the code
> will be stable, then will not be modified.

Hmm. Ok, agreed. I didn't mean the current shape ought to be
changed.

> Thank you for comments, I'll look on it


regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center



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Thank you for the new patch.

- The latest patch is missing xpath_parser.h at least since ns-3. That of the first (not-numbered) version was still
usable.

- c29c578 conflicts on doc/src/sgml/func.sgml


At Sun, 15 Oct 2017 12:06:11 +0200, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRCYBH+a6oJoEYUFDUpBQ1ySwtt2CfnFZxs2Ab9EfONbUQ@mail.gmail.com>
> 2017-10-02 12:22 GMT+02:00 Kyotaro HORIGUCHI <
> horiguchi.kyotaro@lab.ntt.co.jp>:
> 
> > Hi, thanks for the new patch.
> >
> > # The patch is missing xpath_parser.h. That of the first patch was usable.
> >
> > At Thu, 28 Sep 2017 07:59:41 +0200, Pavel Stehule <pavel.stehule@gmail.com>
> > wrote in <CAFj8pRBMQa07a=+qQAVMtz5M_hqkJBhiQSOP76+-BrFDj37pvg@
> > mail.gmail.com>
> > > Hi
> > >
> > > now xpath and xpath_exists supports default namespace too
> >
> > At Wed, 27 Sep 2017 22:41:52 +0200, Pavel Stehule <pavel.stehule@gmail.com>
> > wrote in <CAFj8pRCZ8oneG7g2vxs9ux71n8A9twwUO7zQpJiuz+7RGSpSuw@mail.
> > gmail.com>
> > > > 1. Uniformity among simliar features
> > > >
> > > >   As mentioned in the proposal, but it is lack of uniformity that
> > > >   the xpath transformer is applied only to xmltable and not for
> > > >   other xpath related functions.
> > > >
> > >
> > > I have to fix the XPath function. The SQL/XML function Xmlexists doesn't
> > > support namespaces/
> >
> > Sorry, I forgot to care about that. (And the definition of
> > namespace array is of course fabricated by me). I'd like to leave
> > this to committers.  Anyway it is working but the syntax (or
> > whether it is acceptable) is still arguable.
> >
> > SELECT xpath('/a/text()', '<my:a xmlns:my="http://example.com">
> > test</my:a>',
> >              ARRAY[ARRAY['', 'http://example.com']]);
> > |  xpath
> > | --------
> > |  {test}
> > | (1 row)
> >
> >
> > The internal name is properly rejected, but the current internal
> > name (pgdefnamespace.pgsqlxml.internal) seems a bit too long. We
> > are preserving some short names and reject them as
> > user-defined. Doesn't just 'pgsqlxml' work?
> >
> >
> > Default namespace correctly become to be applied on bare
> > attribute names.
> >
> > > updated doc,
> > > fixed all variants of expected result test file
> >
> > Sorry for one by one comment but I found another misbehavior.
> >
> > create table t1 (id int, doc xml);
> > insert into t1
> >    values
> >    (5, '<rows xmlns="http://x.y"><row><a hoge="haha">50</a></row></
> > rows>');
> > select x.* from t1, xmltable(XMLNAMESPACES('http://x.y' AS x),
> > '/x:rows/x:row' passing t1.doc columns data int PATH
> > 'child::x:a[1][attribute::hoge="haha"]') as x;
> > |  data
> > | ------
> > |    50
> >
> > but the following fails.
> >
> > select x.* from t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'),
> > '/rows/row' passing t1.doc columns data int PATH
> > 'child::a[1][attribute::hoge="haha"]') as x;
> > |  data
> > | ------
> > |
> > | (1 row)
> >
> > Perhaps child::a is not prefixed by the transformation.
> >
> 
> the problem was in unwanted attribute modification. The parser didn't
> detect "attribute::hoge" as attribute. Updated parser does it. I reduce
> duplicated code there more.

It worked as expected. But the comparison of "attribute" is
missing t1.length = 9 so the following expression wrongly passes.

child::a[1][attributeabcdefg::hoge="haha"

It is confusing that is_qual_name becomes true when t2 is not a
"qual name", and the way it treats a double-colon is hard to
understand.

It essentially does inserting the default namespace before
unqualified non-attribute name. I believe we can easily
look-ahead to detect a double colon and it would make things
simpler. Could you consider something like the attached patch?
(applies on top of ns-4 patch.)

> > XPath might be complex enough so that it's worth switching to
> > yacc/lex based transformer that is formally verifiable and won't
> > need a bunch of cryptic tests that finally cannot prove the
> > completeness. synchronous_standy_names is far simpler than XPath
> > but using yacc/lex parser.
> >
> >
> > Anyway the following is nitpicking of the current xpath_parser.c.
> >
> > - NODENAME_FIRSTCHAR allows '-' as the first char but it is
> >   excluded from NameStartChar (https://www.w3.org/TR/REC-
> > xml/#NT-NameStartChar)
> >   I think characters with high-bit set is okay.
> >   Also IS_NODENAME_CHAR should be changed.
> >
> 
> fixed
> 
> 
> > - NODENAME_FIRSTCHAR and IS_NODENAME_CHAR is in the same category
> >   but have different naming schemes. Can these are named in the same way?
> >
> 
> fixed
> 
> 
> > - The current transoformer seems to using up to one token stack
> >   depth. Maybe the stack is needless. (pushed token is always
> >   popped just after)
> >
> 
> fixed

Thank you.

I found another (and should be the last, so sorry..) functional
defect in this. This doesn't add default namespace if the tag
name in a predicate is 'and' or 'or'. It needs to be fixed, or
wrote in the documentation as a restriction. (seem hard to fix
it..)

create table t1 (id int, doc xml);
insert into t1 values (1, '<rows xmlns="http://x.y"><row><val>50</val><and>60</and></row></rows>');
select x.* from t1, xmltable(XMLNAMESPACES('http://x.y' AS x),
'/x:rows/x:row' passing t1.doc columns data int PATH
'x:val[../x:and = 60]') as x;data
------  50
(1 row)
select x.* from t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'),
'/rows/row' passing t1.doc columns data int PATH
'val[../and = 60]') as x;data
------

(1 row)



Other comments are follows.

- Please add more comments. XPATH_TOKEN_NAME in _transformXPath in my patch has more

- Debug output might be needed.

# sorry now time's up. will continue tomorrow.

regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center
diff --git a/src/backend/utils/adt/xpath_parser.c b/src/backend/utils/adt/xpath_parser.c
index f22ec76..1d8d93c 100644
--- a/src/backend/utils/adt/xpath_parser.c
+++ b/src/backend/utils/adt/xpath_parser.c
@@ -41,6 +41,8 @@ typedef enum    XPATH_TOKEN_NAME,    XPATH_TOKEN_STRING,    XPATH_TOKEN_NUMBER,
+    XPATH_TOKEN_COLON,
+    XPATH_TOKEN_DCOLON,    XPATH_TOKEN_OTHER}    XPathTokenType;
@@ -68,6 +70,7 @@ typedef struct ParserData#define IS_NODENAME_CHAR(c)        (IS_NODENAME_FIRSTCHAR(c) || (c) == '-'
||(c) == '.' || \                                 ((c) >= '0' && (c) <= '9'))
 
+#define TOKEN_IS_EMPTY(t)    ((t)->ttype == XPATH_TOKEN_NONE)/* * Returns next char after last char of token - XPath
lexer
@@ -112,6 +115,17 @@ getXPathToken(char *str, XPathTokenInfo * ti)            ti->ttype = XPATH_TOKEN_STRING;        }
+        else if (c == ':')
+        {
+            /* look ahead to detect a doulbe-colon */
+            if (*str == ':')
+            {
+                ti->ttype = XPATH_TOKEN_DCOLON;
+                str++;
+            }
+            else
+                ti->ttype = XPATH_TOKEN_COLON;
+        }        else            ti->ttype = XPATH_TOKEN_OTHER;
@@ -165,6 +179,7 @@ pushXPathToken(XPathParserData * parser, XPathTokenInfo * ti)    memcpy(&parser->buffer, ti,
sizeof(XPathTokenInfo));   parser->buffer_is_empty = false;
 
+    ti->ttype = XPATH_TOKEN_NONE;}/*
@@ -179,6 +194,9 @@ writeXPathToken(StringInfo str, XPathTokenInfo * ti)        appendBinaryStringInfo(str, ti->start,
ti->length);   else        appendStringInfoChar(str, *ti->start);
 
+
+    /* this token is comsumed */
+    ti->ttype = XPATH_TOKEN_NONE;}/*
@@ -192,7 +210,7 @@ _transformXPath(StringInfo str, XPathParserData * parser,{    XPathTokenInfo t1,
t2;
-    bool        token_is_tagname = false;
+    bool        tagname_needs_defnsp = false;    bool        token_is_tagattrib = false;    nextXPathToken(parser,
&t1);
@@ -203,7 +221,11 @@ _transformXPath(StringInfo str, XPathParserData * parser,        {            case
XPATH_TOKEN_NUMBER:           case XPATH_TOKEN_STRING:
 
-                token_is_tagname = false;
+                /*
+                 * string cannot be a tag name. write out it immediately and
+                 * go ahead
+                 */
+                tagname_needs_defnsp = false;                token_is_tagattrib = false;
writeXPathToken(str,&t1);
 
@@ -212,8 +234,6 @@ _transformXPath(StringInfo str, XPathParserData * parser,            case XPATH_TOKEN_NAME:
      {
 
-                    bool        is_qual_name = false;
-                    /* inside predicate ignore keywords "and" "or" */                    if (inside_predicate)
          {
 
@@ -226,53 +246,56 @@ _transformXPath(StringInfo str, XPathParserData * parser,                        }
   }
 
-                    token_is_tagname = true;
+                    /* look ahead what is following the name token */
+                    tagname_needs_defnsp = true;                    nextXPathToken(parser, &t2);
-                    if (t2.ttype == XPATH_TOKEN_OTHER)
+                    if (t2.ttype == XPATH_TOKEN_COLON)
+                    {
+                        /* t1 is a quilified node name. no need to add default one. */
+                        tagname_needs_defnsp = false;
+                        writeXPathToken(str, &t1);    /* namespace name */
+                        writeXPathToken(str, &t2);    /* colon */
+                        /* get node name */
+                        nextXPathToken(parser, &t1);
+                    }
+                    else if (t2.ttype == XPATH_TOKEN_DCOLON)
+                    {
+                        /* t1 is an axis name. write out as it is */
+                        if (strncmp(t1.start, "attribute", 9) == 0 && t1.length == 9)
+                            token_is_tagattrib = true;
+
+                        writeXPathToken(str, &t1);    /* axis name */
+                        writeXPathToken(str, &t2);    /* double colon */
+
+                        /*
+                         * The next token may be qualified tag name, process
+                         * it as a fresh token.
+                         */
+                        nextXPathToken(parser, &t1);
+                        break;
+                    }
+                    else if (t2.ttype == XPATH_TOKEN_OTHER)                    {
+                        /* function name doesn't require namespace */                        if (*t2.start == '(')
-                            token_is_tagname = false;
-                        else if (*t2.start == ':')
-                        {
-                            XPathTokenInfo t3;
-
-                            nextXPathToken(parser, &t3);
-                            if (t3.ttype == XPATH_TOKEN_OTHER && *t3.start == ':'
-                                     && strncmp(t1.start, "attribute", 9) == 0)
-                            {
-                                /* other syntax for attribute, where we should not apply def namespace */
-                                appendStringInfo(str, "attribute::");
-                                nextXPathToken(parser, &t1);
-                                token_is_tagattrib = true;
-                                break;
-                            }
-                            else
-                            {
-                                pushXPathToken(parser, &t3);
-                                is_qual_name = true;
-                            }
-                        }
+                            tagname_needs_defnsp = false;
+                        else
+                            pushXPathToken(parser, &t2);                    }
-                    if (token_is_tagname && !token_is_tagattrib
-                                 && !is_qual_name && def_namespace_name != NULL)
+                    if (tagname_needs_defnsp && !token_is_tagattrib &&
+                        def_namespace_name != NULL)                        appendStringInfo(str, "%s:",
def_namespace_name);                   token_is_tagattrib = false;
 
-                    writeXPathToken(str, &t1);
+                    /* write maybe-tagname if not consumed */
+                    if (!TOKEN_IS_EMPTY(&t1))
+                        writeXPathToken(str, &t1);
-                    if (is_qual_name)
-                    {
+                    /* output t2 if not consumed yet */
+                    if (!TOKEN_IS_EMPTY(&t2))                        writeXPathToken(str, &t2);
-                        nextXPathToken(parser, &t1);
-                        if (t1.ttype == XPATH_TOKEN_NAME)
-                            writeXPathToken(str, &t1);
-                        else
-                            pushXPathToken(parser, &t1);
-                    }
-                    else
-                        pushXPathToken(parser, &t2);                    nextXPathToken(parser, &t1);                }
@@ -283,7 +306,6 @@ _transformXPath(StringInfo str, XPathParserData * parser,                    char        c =
*t1.start;                   token_is_tagattrib = false;
 
-                    token_is_tagname = false;                    writeXPathToken(str, &t1);
@@ -307,10 +329,14 @@ _transformXPath(StringInfo str, XPathParserData * parser,                }                break;
+            case XPATH_TOKEN_COLON:
+            case XPATH_TOKEN_DCOLON:            case XPATH_TOKEN_NONE:                elog(ERROR, "should not be
here");       }    }
 
+
+    elog(LOG, "\"%s\"", str->data);}void

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On Thu, Nov 9, 2017 at 10:11 PM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> Attached new version.

Hi Pavel,

FYI my patch testing robot says[1]:
    xml                      ... FAILED

regression.diffs says:

+ SELECT x.* FROM t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'),
'/rows/row' PASSING t1.doc COLUMNS data int PATH
'child::a[1][attribute::hoge="haha"]') as x;
+ data
+ ------
+ (0 rows)
+

Maybe you forgot to git-add the expected file?

[1] https://travis-ci.org/postgresql-cfbot/postgresql/builds/305979133

-- 
Thomas Munro
http://www.enterprisedb.com

On Sat, Nov 25, 2017 at 2:32 AM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> fixed regress test

The last patch still applies, but did not get any reviews.
Horiguchi-san, you are marked as a reviewer of this patch. Could you
look at it? For now, I am moving it to next CF.
-- 
Michael

At Wed, 29 Nov 2017 14:33:08 +0900, Michael Paquier <michael.paquier@gmail.com> wrote in
<CAB7nPqROox3HnfjTGhKo4NA97oX8g1DSr0LULWVYsaKHuYqZEw@mail.gmail.com>
> On Sat, Nov 25, 2017 at 2:32 AM, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> > fixed regress test
> 
> The last patch still applies, but did not get any reviews.
> Horiguchi-san, you are marked as a reviewer of this patch. Could you
> look at it? For now, I am moving it to next CF.

Sorry for the absense. It is near to complete. I'll look this soon.

regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center

Hello, I returned to this.

I thouroughly checked the translator's behavior against the XPath
specifications and checkd out the documentation and regression
test. Almost everything is fine for me and this would be the last
comment from me.

At Fri, 24 Nov 2017 18:32:43 +0100, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRB7Fs_2DrtUTGhTmQb+KReXPH6SG62hGWO3KVL_eZYCaA@mail.gmail.com>
> 2017-11-24 18:13 GMT+01:00 Pavel Stehule <pavel.stehule@gmail.com>:
> 
> >
> >
> > 2017-11-24 17:53 GMT+01:00 Pavel Stehule <pavel.stehule@gmail.com>:
> >
> >> Hi
> >>
> >> 2017-11-22 22:49 GMT+01:00 Thomas Munro <thomas.munro@enterprisedb.com>:
> >>
> >>> On Thu, Nov 9, 2017 at 10:11 PM, Pavel Stehule <pavel.stehule@gmail.com>
> >>> wrote:
> >>> > Attached new version.
> >>>
> >>> Hi Pavel,
> >>>
> >>> FYI my patch testing robot says[1]:
> >>>
> >>>      xml                      ... FAILED
> >>>
> >>> regression.diffs says:
> >>>
> >>> + SELECT x.* FROM t1, xmltable(XMLNAMESPACES(DEFAULT 'http://x.y'),
> >>> '/rows/row' PASSING t1.doc COLUMNS data int PATH
> >>> 'child::a[1][attribute::hoge="haha"]') as x;
> >>> + data
> >>> + ------
> >>> + (0 rows)
> >>> +
> >>>
> >>> Maybe you forgot to git-add the expected file?
> >>>
> >>> [1] https://travis-ci.org/postgresql-cfbot/postgresql/builds/305979133
> >>
> >>
> >> unfortunately xml.out has 3 versions and is possible so one version
> >> should be taken elsewhere than my comp.
> >>
> >> please can me send your result xml.out file?
> >>
> >
> > looks like this case is without xml support so I can fix on my comp.
> >
> >
> fixed regress test

(I wouldn't have found that..)

I have three comments on the behavior and one on documentation.

1. Lack of syntax handling.

["'" [^'] "'"] is also a string literal, but getXPathToken is
forgetting that and applying default namespace mistakenly to the
astring content.

2. Additional comment might be good.

It might be better having additional description about default
namespace in the comment starts from "Namespace mappings are
passed as text[]" in xpth_internal().

3. Inconsistent behavior from named namespace.

| -     function context, aliases are <emphasis>local</emphasis>).
| +     function context, aliases are <emphasis>local</emphasis>). Default namespace has
| +     empty name (empty string) and should be only one.

This works as the description, on the other hand the same
namespace prefix can be defined twice or more in the array and
the last one is in effect. I don't see a reason for
differenciating the default namespace case.


4. Comments on the documentation part.

# Even though I'm not sutable for commenting on wording...

| +     Inside predicate literals <literal>and</literal>, <literal>or</literal>,
| +     <literal>div</literal> and <literal>mod</literal> are used as keywords
| +     (XPath operators) every time and default namespace are not applied there.

*I*'d like to have a comma between the predicate and literals,
and have a 'a' before prediate. Or 'Literals .. inside a
predicate' might be better?

'are used as keywords' might be better being 'are identifed as
keywords'?

Default namespace is applied to tag names except the listed
keywords even inside a predicate. So 'are not applied there'
might be better being 'are not applied to them'?  Or 'are not
applied in the case'?

| +     If you would to use these literals like tag names, then the default namespace
| +     should not be used, and these literals should be explicitly
| +     labeled.
| +    </para>

Default namespace is not applied *only to* such keywords inside a
predicate. Even if an Xpath expression contains such a tag name,
default namespace still works for other tags. Does the following
make sense?

+ Use named namespace to qualify such tag names appear in an
+ XPath predicate.



===
After the aboves are addressed (even or rejected), I think I
don't have no additional comment.


- This current patch applies safely (with small shifts) on the
  current master.

- The code looks fine for me.

- This patch translates the given XPath expression by prefixing
  unprefixed tag names with a special namespace prefix only in
  the case where default namespace is defined, so the existing
  behavior is not affected.

- The syntax is existing but just not implemented so I don't
  think no arguemnts needed here.

- It undocumentedly inhibits the usage of the namespace prefix
  "pgdefnamespace.pgsqlxml.internal" but I believe no one can
  notice that.

- The default-ns translator (xpath_parser.c) seems working
  perfectly with some harmless exceptions.

  (xpath specifications is here: https://www.w3.org/TR/1999/REC-xpath-19991116/)

  Related unused features (and not documented?):
    context variables ($n notations), 
    user-defined functions (or function names prefixed by a namespace prefix)

  Newly documented behavior:
    the default namespace isn't applied to and/or/div/mod.

- Dodumentation looks enough.

- Regression test doesn't cover the XPath syntax but it's not
  viable.  I am fine with the basic test cases added by the
  current patch.

regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center

Hello.

At Wed, 24 Jan 2018 10:30:39 +0100, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRBVUVvG1CXxgrs0UipTziUX6M788z-=L9gQvwAB4UGLeg@mail.gmail.com>
> Hi
> 
> 2018-01-23 8:13 GMT+01:00 Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp
> > I have three comments on the behavior and one on documentation.
> >
> > 1. Lack of syntax handling.
> >
> > ["'" [^'] "'"] is also a string literal, but getXPathToken is
> > forgetting that and applying default namespace mistakenly to the
> > astring content.
> >
> 
> In this case, I am not sure if I understand well.
> 
> Within expressions, literal strings are delimited by single or double
> quotation marks, which are also used to delimit XML attributes. To avoid a
> quotation mark in an expression being interpreted by the XML processor as
> terminating the attribute value the quotation mark can be entered as a
> character reference (" or '). Alternatively, the expression can
> use single quotation marks if the XML attribute is delimited with double
> quotation marks or vice-versa.

I think it is correct understanding.

> So if I understand well, then XML string can looks like ' some " some ' or
> " some ' some ". I fixed it.

Thanks. It looks good.

> > 2. Additional comment might be good.
> >
> > It might be better having additional description about default
> > namespace in the comment starts from "Namespace mappings are
> > passed as text[]" in xpth_internal().
> >
> 
> fixed

Thanks.


> > 3. Inconsistent behavior from named namespace.
> >
> > | -     function context, aliases are <emphasis>local</emphasis>).
> > | +     function context, aliases are <emphasis>local</emphasis>). Default
> > namespace has
> > | +     empty name (empty string) and should be only one.
> >
> > This works as the description, on the other hand the same
> > namespace prefix can be defined twice or more in the array and
> > the last one is in effect. I don't see a reason for
> > differenciating the default namespace case.
> >
> 
> It looks like libxml2 bug. There is no sense to use more than one default
> namespace, and although it is inconsistent with other namespaces, I am
> thinking so it is correct. Is better to raise error early. In this case
> Postgres expects so libxml2 ensure all namespace checks and it is tolerant.
> Default namespace is implemented inside Postgres, and I don't see any
> advantage of tolerant behave. More default namespaces is disallowed for
> XMLTABLE - so some inconsistency there should be. In this case I prefer
> raise error to signalize ambiguous or badly formatted input clearly.

Ok. I'm fine with that.

> > 4. Comments on the documentation part.
> >
> > # Even though I'm not sutable for commenting on wording...
> >
> > | +     Inside predicate literals <literal>and</literal>,
> > <literal>or</literal>,
> > | +     <literal>div</literal> and <literal>mod</literal> are used as
> > keywords
> > | +     (XPath operators) every time and default namespace are not applied
> > there.
> >
> > *I*'d like to have a comma between the predicate and literals,
> > and have a 'a' before prediate. Or 'Literals .. inside a
> > predicate' might be better?
> >
> 
> fixed
> 
> >
> > 'are used as keywords' might be better being 'are identifed as
> > keywords'?
> >
> 
> fixed
> 
> 
> > Default namespace is applied to tag names except the listed
> > keywords even inside a predicate. So 'are not applied there'
> > might be better being 'are not applied to them'?  Or 'are not
> > applied in the case'?
> >
> > | +     If you would to use these literals like tag names, then the
> > default namespace
> > | +     should not be used, and these literals should be explicitly
> > | +     labeled.
> > | +    </para>
> >
> > Default namespace is not applied *only to* such keywords inside a
> > predicate. Even if an Xpath expression contains such a tag name,
> > default namespace still works for other tags. Does the following
> > make sense?
> >
> > + Use named namespace to qualify such tag names appear in an
> > + XPath predicate.
> >
> >
> fixed
> 
> I hope so some native speaker finalize doc. It is out of my knowledges
> .

I am also anxious for that.


> > ===
> > After the aboves are addressed (even or rejected), I think I
> > don't have no additional comment.
> >
> >
> > - This current patch applies safely (with small shifts) on the
> >   current master.
> >
> > - The code looks fine for me.
> >
> > - This patch translates the given XPath expression by prefixing
> >   unprefixed tag names with a special namespace prefix only in
> >   the case where default namespace is defined, so the existing
> >   behavior is not affected.
> >
> > - The syntax is existing but just not implemented so I don't
> >   think no arguemnts needed here.
> >
> > - It undocumentedly inhibits the usage of the namespace prefix
> >   "pgdefnamespace.pgsqlxml.internal" but I believe no one can
> >   notice that.
> >
> > - The default-ns translator (xpath_parser.c) seems working
> >   perfectly with some harmless exceptions.
> >
> >   (xpath specifications is here: https://www.w3.org/TR/1999/
> > REC-xpath-19991116/)
> >
> >   Related unused features (and not documented?):
> >     context variables ($n notations),
> >     user-defined functions (or function names prefixed by a namespace
> > prefix)
> 
> 
> I did some fast check - and these features are not supported by libxml2 -
> so it is question if it should be parsed by out xpath parser. So there are
> not possible to check it, test it :(

I'm fine with that. I don't think that test for them is needed
since PostgreSQL doesn't support them anyway. Sorry for the
confusing comment. (libxml2 complains about that in the following
way.)

 | =# select xpath('/a/text()=$', '<a>test</a>');
 | ERROR:  invalid XPath expression
!| DETAIL:  Expected $ for variable reference
 | CONTEXT:  SQL function "xpath" statement 1

 | =# select xpath('func(/a/text())', '<a>test</a>');
 | ERROR:  could not create XPath object
!| DETAIL:  Unregistered function
 | CONTEXT:  SQL function "xpath" statement 1

> >   Newly documented behavior:
> >     the default namespace isn't applied to and/or/div/mod.
> >
> > - Dodumentation looks enough.
> >
> > - Regression test doesn't cover the XPath syntax but it's not
> >   viable.  I am fine with the basic test cases added by the
> >   current patch.
> >
> > regards,
> >
> 
> I am sending updated version.
> 
> Very much thanks for very precious review

It's my pleasure. Sorry for my slow responses.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center

Hello. I reviewed this and think that this is in Ready for
Committer stage.

The patch is available here.

https://www.postgresql.org/message-id/CAFj8pRBVUVvG1CXxgrs0UipTziUX6M788z-%3DL9gQvwAB4UGLeg%40mail.gmail.com

The following list consists of the same items in upthread message
as confirmation.

- This applies to the current master HEAD cleanly.

- The code looks fine.

- This patch translates the given XPath expression by prefixing
  unprefixed tag names with a special namespace prefix only in
  the case where default namespace is defined, so the existing
  behavior is not affected.

- The syntax of default namespace is existing but just not usable
  so I don't think no arguemnts needed here.

- It undocumentedly inhibits the usage of the namespace prefix
  "pgdefnamespace.pgsqlxml.internal" but I believe no one can
  notice that.

- The default-ns translator (xpath_parser.c) seems working
  perfectly with some harmless exceptions.  (Behavior about
  context variables and user-defined xml functions, which are not
  handled by PostgreSQL.)

- Dodumentation looks enough.

- Regression test doesn't cover the XPath syntax but I think it's
  not viable.  I am fine with the basic test cases added by the
  current patch.

regards,

-- 
Kyotaro Horiguchi
NTT Open Source Software Center

On 01/24/2018 04:30 AM, Pavel Stehule wrote:
>
> I am sending updated version.
>
> Very much thanks for very precious review
>
>



Thomas,

I am unable to replicate the Linux failure seen in the cfbot on my 
Fedora machine. Both when building with libxml2 and without, after 
applying the latest patch the tests pass without error. Can you please 
investigate what's going on here?

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

On Fri, Aug 10, 2018 at 6:26 AM Andrew Dunstan
<andrew.dunstan@2ndquadrant.com> wrote:
> On 01/24/2018 04:30 AM, Pavel Stehule wrote:
> >
> > I am sending updated version.
> >
> > Very much thanks for very precious review
>
> Thomas,
>
> I am unable to replicate the Linux failure seen in the cfbot on my
> Fedora machine. Both when building with libxml2 and without, after
> applying the latest patch the tests pass without error. Can you please
> investigate what's going on here?

Well this is strange...  I can't reproduce the problem either with or
without --with-libxml on a Debian box (was trying to get fairly close
to the OS that Travis runs on).  But I see the same failure when I
apply the patch on my FreeBSD 12 laptop and test without
--with-libxml.  Note that when cfbot runs it, the patch is applied
with FreeBSD patch, and then it's tested without --with-libxml on
Ubuntu (Travis's default OS).  [Side note: I should change it to build
--with-libxml, but that's not the point.]  So the common factor is a
different patch implementation.  I wonder if a hunk is being
misinterpreted.

-- 
Thomas Munro
http://www.enterprisedb.com

On Mon, Sep 17, 2018 at 5:36 PM Pavel Stehule <pavel.stehule@gmail.com> wrote:
> po 17. 9. 2018 v 2:05 odesílatel Thomas Munro <thomas.munro@enterprisedb.com> napsal:
>> On Fri, Aug 10, 2018 at 6:26 AM Andrew Dunstan
>> <andrew.dunstan@2ndquadrant.com> wrote:
>> > On 01/24/2018 04:30 AM, Pavel Stehule wrote:
>> > >
>> > > I am sending updated version.
>> > >
>> > > Very much thanks for very precious review
>> >
>> > Thomas,
>> >
>> > I am unable to replicate the Linux failure seen in the cfbot on my
>> > Fedora machine. Both when building with libxml2 and without, after
>> > applying the latest patch the tests pass without error. Can you please
>> > investigate what's going on here?
>>
>> Well this is strange...  I can't reproduce the problem either with or
>> without --with-libxml on a Debian box (was trying to get fairly close
>> to the OS that Travis runs on).  But I see the same failure when I
>> apply the patch on my FreeBSD 12 laptop and test without
>> --with-libxml.  Note that when cfbot runs it, the patch is applied
>> with FreeBSD patch, and then it's tested without --with-libxml on
>> Ubuntu (Travis's default OS).  [Side note: I should change it to build
>> --with-libxml, but that's not the point.]  So the common factor is a
>> different patch implementation.  I wonder if a hunk is being
>> misinterpreted.
>
>
> This patch is not too large. Please, can me send a related files, I can check it manually.

I confirmed that xml_1.out is different depending on which 'patch' you
use.  I've attached the output from FreeBSD patch 2.0-12u11 and GNU
patch 2.5.8.  It's an interesting phenomenon, probably due to having a
huge long file with a lot of repeated text and a slightly different
algorithms or parameters, but I don't think you need to worry about it
for this.  Sorry for the distraction.

--
Thomas Munro
http://www.enterprisedb.com

Pavel Stehule <pavel.stehule@gmail.com> writes:
> [ xml-xpath-default-ns-7.patch ]

At Andrew's prompting, I took a look over this patch.  I don't know much
of anything about XML, so I have no idea as to standards compliance here,
but I do have some comments:

* I'm fairly uncomfortable with the idea that we're going to maintain
our own XPath parser.  That seems like a recipe for lots of future
work ... and the code is far too underdocumented for anyone to actually
maintain it.  (Case in point: _transformXPath's arguments are not
documented at all, and in fact there's hardly a word about what it's
even supposed to *do*.)

* I think the business with "pgdefnamespace.pgsqlxml.internal" is just
plain awful.  It's a wart, and I don't think it's even saving you any
code once you account for all the places where you have to throw errors
for somebody trying to use that as a regular name.  This should be done
with out-of-band signaling if possible.  The existing convention above
this code is that a NULL pointer means a default namespace; can't that
be continued throughout?  If that's not practical, can you pick a string
that simply can't syntactically be a namespace name?  (In the SQL world,
for example, an empty string is an illegal identifier so that that could
be used for the purpose.  But I don't know if that applies to XML.)
Or perhaps you can build a random name that is chosen just to make it
different from any of the listed namespaces?  If none of those work,
I think passing around an explicit "isdefault" boolean alongside the name
would be better than having a reserved word.

* _transformXPath recurses, so doesn't it need check_stack_depth()?

* I'm not especially in love with using function names that start
with an underscore.  I do not think that adds anything, and it's
unlike the style in most places in PG.

* This is a completely unhelpful error message:
+    if (!parser->buffer_is_empty)
+        elog(ERROR, "internal error");
If you can't be bothered to write a message that says something
useful, either drop the test or turn it into an Assert.  I see some
other internal errors that aren't up to project norms either.

* Either get rid of the "elog(DEBUG1)"s, or greatly lower their
message priority.  They might've been appropriate for developing
this patch, but they are not okay to commit that way.

* Try to reduce the amount of random whitespace changes in the patch.

* .h files should never #include "postgres.h", per project policy.

* I'm not sure I'd bother with putting the new code into a separate
file rather than cramming it into xml.c.  The main reason why not
is that you're going to get "empty translation unit" warnings from
some compilers in builds without USE_LIBXML.

* Documentation, comments, and error messages could all use some
copy-editing by a native English speaker (you knew that of course).

            regards, tom lane

> On Fri, Sep 21, 2018 at 1:30 PM Pavel Stehule <pavel.stehule@gmail.com> wrote:
>
> Thank you for comments
>
> Attached updated patch

Unfortunately, current version of the patch doesn't pass make check, something
is missing for xml tests. Could you please rebase it?

After that I hope someone from reviewers (Kyotaro?) can probably confirm if
it's still in a good shape. For now I'm moving it to the next CF.

Hello.

At Fri, 30 Nov 2018 07:48:26 +0100, Pavel Stehule <pavel.stehule@gmail.com> wrote in
<CAFj8pRD7Zg07t4NpZu09T4RgXz0bTvyYg2eMVoH+o_drNoiz6w@mail.gmail.com>
> Hi
> 
> čt 29. 11. 2018 v 14:44 odesílatel Dmitry Dolgov <9erthalion6@gmail.com>
> napsal:
> 
> > > On Fri, Sep 21, 2018 at 1:30 PM Pavel Stehule <pavel.stehule@gmail.com>
> > wrote:
> > >
> > > Thank you for comments
> > >
> > > Attached updated patch
> >
> > Unfortunately, current version of the patch doesn't pass make check,
> > something
> > is missing for xml tests. Could you please rebase it?
> >
> > After that I hope someone from reviewers (Kyotaro?) can probably confirm if
> > it's still in a good shape. For now I'm moving it to the next CF.

Sure. Sorry for coming late. I reconfirmed this.

The most significant change in this version is namespace name
generaton.

- We can remove strlen from mutate_name by mutating the string in
  reverse order. We don't need to mutate it in a human-affinity
  order. The name would be 1-letter in almost all cases.

  Concretely, the order in my mind is the follows:

  "" "a" "b" ..."z" "aa" "ba" "ca"... "za" "ab"..

- Might the 'propriety' correctly be 'properties'?

 +     /* register namespace if all propriety are available */


- Is the "if" a mistake of "in"?

 +     * collect ns names if ResTarget format for possible usage
 +     * in getUniqNames function.


- I suppose the following should be like "register default
  namespace definition if any".

 +    /* get default namespace name when it is required */


Maybe the followings are not new. (Note that I'm not a naitive speaker.)

- I cannot read this. (I might be to blame..)

  + * default namespace for XPath expressions. Because there are not any API
  + * how to transform or access to parsed XPath expression we have to parse
  + * XPath here.

- This might need to explain "by what".

 + * Those functionalities are implemented with a simple XPath parser/
 + * preprocessor. This XPath parser transforms a XPath expression to another
 + * XPath expression that can be used by libxml2 XPath evaluation. It doesn't
 + * replace libxml2 XPath parser or libxml2 XPath expression evaluation.

- "add" -> "adds", "def_namespace_name" seems to need to be
  replaced with something else.

 + * This transformation add def_namespace_name to any unqualified node name
 + * or attribute name of xpath expression.

(Sorry, I'll look further later.)

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center

Hi,

On 2018-09-18 11:33:38 -0400, Tom Lane wrote:
> Pavel Stehule <pavel.stehule@gmail.com> writes:
> > [ xml-xpath-default-ns-7.patch ]
> 
> At Andrew's prompting, I took a look over this patch.  I don't know much
> of anything about XML, so I have no idea as to standards compliance here,
> but I do have some comments:
> 
> * I'm fairly uncomfortable with the idea that we're going to maintain
> our own XPath parser.  That seems like a recipe for lots of future
> work ... and the code is far too underdocumented for anyone to actually
> maintain it.  (Case in point: _transformXPath's arguments are not
> documented at all, and in fact there's hardly a word about what it's
> even supposed to *do*.)

We were looking at this patch at the pgday developer meeting: Our
impression is that this patch should be rejected. If really desired, the
best approach seems to be actually implement this in libxml, and then go
from there.

Greetings,

Andres Freund

On Thu, Jan 31, 2019 at 02:54:49PM +0100, Pavel Stehule wrote:
> Unfortunately,  the development of libxml2 is frozen.
>
> I have to accept it.

And marked as rejected, based on the last consensus.
--
Michael