Skip site navigation (1) Skip section navigation (2)

Re: patch: function xmltable

From: Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
To: Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
Cc: Craig Ringer <craig(at)2ndquadrant(dot)com>, PostgreSQL Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: patch: function xmltable
Date: 2017-01-14 13:43:26
Message-ID: CAFj8pRA2UCwquoqxx38QFLMPxDPT=h9nNFq02fYaEVqh=-RJNQ@mail.gmail.com (view raw, whole thread or download thread mbox)
Thread:
Lists: pgsql-hackers
Hi

2017-01-13 21:32 GMT+01:00 Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>:

> Pavel Stehule wrote:
> >
> > I used your proposed way based on Restarget
>
> Thanks.  Some more tweaking to go yet before I consider this
> committable, but it's much better now.  Here's v28.  I changed a few
> things:
>
> - make expression evaluation code more orthodox:
>   1. avoid PG_TRY, use a ExprContext shutdown callback instead
>   2. use a "Fast" evaluator, for calls past the first one
>   3. don't look up fmgrinfos until execution time
>   4. don't duplicate get_expr_result_type
> - make parser accept DEFAULT namespace. Only xml implementation barfs.
>   (this means we lost the errposition pointer, but I don't really
>    care. We could fix it if we cared)
> - clean up parse analysis code a little bit
> - move decls/struct defs to better locations in source code
> - remove leftover "namespaces" in TableExprState
> - pgindent the whole mess.
>
>
I checked the changes and looks correct - although for some I had not
courage :) - like dynamic change of exprstate->evalfunc

I fixed test, and append forgotten header file




> I don't like the xml.c code and the "evalcols" flag.  That's next on my
> list to fix.
>

You need some flag to specify if column paths are valid or not.


> I don't think to_xmlstr() is necessary, considering xml_text2xmlChar.
> We could just apply a cast of the source cstring to xmlChar.
>

is it safe? For one byte encodings?

Regards

Pavel


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

Attachment: xmltable-29.patch
Description: text/x-patch (163.5 KB)

In response to

Responses

pgsql-hackers by date

Next:From: Peter EisentrautDate: 2017-01-14 14:19:14
Subject: Re: Re: Clarifying "server starting" messaging in pg_ctl start without --wait
Previous:From: Gilles DaroldDate: 2017-01-14 13:02:40
Subject: Re: Patch to implement pg_current_logfile() function

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group