This wasn't addressed in the original patch, but it doesn't take very
much additional code to cover the case, so let's get it done.
Since pg_trgm 1.1 hasn't been released yet, I just changed the definition
of what's in it, rather than inventing a 1.2.
This works by extracting trigrams from the given regular expression,
in generally the same spirit as the previously-existing support for
LIKE searches, though of course the details are far more complicated.
Currently, only GIN indexes are supported. We might be able to make
it work with GiST indexes later.
The implementation includes adding API functions to backend/regex/
to provide a view of the search NFA created from a regular expression.
These functions are meant to be generic enough to be supportable in
a standalone version of the regex library, should that ever happen.
Alexander Korotkov, reviewed by Heikki Linnakangas and Tom Lane
Unlike Btree-based LIKE optimization, this works for non-left-anchored
search patterns. The effectiveness of the search depends on how many
trigrams can be extracted from the pattern. (The worst case, with no
trigrams, degrades to a full-table scan, so this isn't a panacea. But
it can be very useful.)
Alexander Korotkov, reviewed by Jan Urbanski
Block elements with verbatim formatting (literallayout, programlisting,
screen, synopsis) should be aligned at column 0 independent of the surrounding
SGML, because whitespace is significant, and indenting them creates erratic
whitespace in the output. The CSS stylesheets already take care of indenting
the output.
Assorted markup improvements to go along with it.
to ensure that the resulting webpages have predictable URLs, instead of
ever-changing numeric IDs. The new contrib docs were the biggest
offender, but some old stuff had the problem too. Also, rename a couple
of new contrib sgml files for consistency's sake.
Bruce Momjian
Tom Lane
Peter Eisentraut
Magnus Hagander