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Previously, -j caused the entire input file to be read in and executed as a single command string. That's undesirable, not least because any error causes the entire file to be regurgitated as the "failing query". Some experimentation suggests a better rule: end the command string when we see a semicolon immediately followed by two newlines, ie, an empty line after a query. This serves nicely to break up the existing examples such as information_schema.sql and system_views.sql. A limitation is that it's no longer possible to write such a sequence within a string literal or multiline comment in a file meant to be read with -j; but there are no instances of such a problem within the data currently used by initdb. (If someone does make such a mistake in future, it'll be obvious because they'll get an unterminated-literal or unterminated-comment syntax error.) Other than that, there shouldn't be any negative consequences; you're not forced to end statements that way, it's just a better idea in most cases. In passing, remove src/include/tcop/tcopdebug.h, which is dead code because it's not included anywhere, and hasn't been for more than ten years. One of the debug-support symbols it purported to describe has been unreferenced for at least the same amount of time, and the other is removed by this commit on the grounds that it was useless: forcing -j mode all the time would have broken initdb. The lack of complaints about that, or about the missing inclusion, shows that no one has tried to use TCOP_DONTUSENEWLINE in many years.
src/backend/snowball/README
Snowball-Based Stemming
=======================
This module uses the word stemming code developed by the Snowball project,
http://snowball.tartarus.org/
which is released by them under a BSD-style license.
The files under src/backend/snowball/libstemmer/ and
src/include/snowball/libstemmer/ are taken directly from their libstemmer_c
distribution, with only some minor adjustments of file inclusions. Note
that most of these files are in fact derived files, not master source.
The master sources are in the Snowball language, and are available along
with the Snowball-to-C compiler from the Snowball project. We choose to
include the derived files in the PostgreSQL distribution because most
installations will not have the Snowball compiler available.
To update the PostgreSQL sources from a new Snowball libstemmer_c
distribution:
1. Copy the *.c files in libstemmer_c/src_c/ to src/backend/snowball/libstemmer
with replacement of "../runtime/header.h" by "header.h", for example
for f in libstemmer_c/src_c/*.c
do
sed 's|\.\./runtime/header\.h|header.h|' $f >libstemmer/`basename $f`
done
(Alternatively, if you rebuild the stemmer files from the master Snowball
sources, just omit "-r ../runtime" from the Snowball compiler switches.)
2. Copy the *.c files in libstemmer_c/runtime/ to
src/backend/snowball/libstemmer, and edit them to remove direct inclusions
of system headers such as <stdio.h> --- they should only include "header.h".
(This removal avoids portability problems on some platforms where <stdio.h>
is sensitive to largefile compilation options.)
3. Copy the *.h files in libstemmer_c/src_c/ and libstemmer_c/runtime/
to src/include/snowball/libstemmer. At this writing the header files
do not require any changes.
4. Check whether any stemmer modules have been added or removed. If so, edit
the OBJS list in Makefile, the list of #include's in dict_snowball.c, and the
stemmer_modules[] table in dict_snowball.c.
5. The various stopword files in stopwords/ must be downloaded
individually from pages on the snowball.tartarus.org website.
Be careful that these files must be stored in UTF-8 encoding.