Given
https://www.postgresql.org/message-id/20170116210019.a3glfwspg5lnfrnm@alap3.anarazel.de
which is going to heavily change how the executor works in this area, I
am returning this patch to you again. I would like a few rather minor
changes:
1. to_xmlstr can be replaced with calls to xmlCharStrdup.
2. don't need xml_xmlnodetostr either -- just use xml_xmlnodetoxmltype (which returns text*) and extract the cstring
fromthe varlena. It's a bit more wasteful in terms of cycles, but I don't think we care. If we do care, change the
functionso that it returns cstring, and have the callers that want text wrap it in cstring_to_text.
3. have a new perValueCxt memcxt in TableExprState, child of buildercxt, and switch to it just before GetValue()
(resetit just before switching). Then, don't worry about leaks in GetValue. This way, the text* conversions et al
don'tmatter.
After that I think we're going to need to get this working on top of
Andres' changes. Which I'm afraid is going to be rather major surgery,
but I haven't looked.
--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services