Very minor comment here: these SGML "id" tags:
+ <refentry id="SQL-ALTEREXTENSIONTEMPLATE">
are pretty important, because they become the URL for the specific page
in the reference docs. So I think you should fix them to be the correct
spelling of the command "alter template for extension", and also perhaps
add an hyphen or two. Maybe "SQL-ALTER-EXTENSION-FOR-TEMPLATE". (We're
inconsistent about adding hyphens; most URLs don't have hyphens after
then "sql-" bit, so "sql-altertablespace", but we have some examples of
the opposite such as "sql-commit-prepared" and "sql-drop-owned".)
--
Álvaro Herrera http://www.2ndQuadrant.com/
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