accesses versus sequential accesses, a (very crude) estimate of the
effects of caching on random page accesses, and cost to evaluate WHERE-
clause expressions. Export critical parameters for this model as SET
variables. Also, create SET variables for the planner's enable flags
(enable_seqscan, enable_indexscan, etc) so that these can be controlled
more conveniently than via PGOPTIONS.
Planner now estimates both startup cost (cost before retrieving
first tuple) and total cost of each path, so it can optimize queries
with LIMIT on a reasonable basis by interpolating between these costs.
Same facility is a win for EXISTS(...) subqueries and some other cases.
Redesign pathkey representation to achieve a major speedup in planning
(I saw as much as 5X on a 10-way join); also minor changes in planner
to reduce memory consumption by recycling discarded Path nodes and
not constructing unnecessary lists.
Minor cleanups to display more-plausible costs in some cases in
EXPLAIN output.
Initdb forced by change in interface to index cost estimation
functions.
pghackers discussion of 5-Jan-2000. The amopselect and amopnpages
estimators are gone, and in their place is a per-AM amcostestimate
procedure (linked to from pg_am, not pg_amop).
As Bruce mentioned, this is due to the conflict among changes we made.
Included patches should fix the problem(I changed all MB to
MULTIBYTE). Please let me know if you have further problem.
P.S. I did not include pathces to configure and gram.c to save the
file size(configure.in and gram.y modified).
From: t-ishii@sra.co.jp
Attached are patches to enhance the multi-byte support. (patches are
against 7/18 snapshot)
* determine encoding at initdb/createdb rather than compile time
Now initdb/createdb has an option to specify the encoding. Also, I
modified the syntax of CREATE DATABASE to accept encoding option. See
README.mb for more details.
For this purpose I have added new column "encoding" to pg_database.
Also pg_attribute and pg_class are changed to catch up the
modification to pg_database. Actually I haved added pg_database_mb.h,
pg_attribute_mb.h and pg_class_mb.h. These are used only when MB is
enabled. The reason having separate files is I couldn't find a way to
use ifdef or whatever in those files. I have to admit it looks
ugly. No way.
* support for PGCLIENTENCODING when issuing COPY command
commands/copy.c modified.
* support for SQL92 syntax "SET NAMES"
See gram.y.
* support for LATIN2-5
* add UNICODE regression test case
* new test suite for MB
New directory test/mb added.
* clean up source files
Basic idea is to have MB's own subdirectory for easier maintenance.
These are include/mb and backend/utils/mb.
I have implemented a framework of encoding translation between the
backend and the frontend. Also I have added a new variable setting
command:
SET CLIENT_ENCODING TO 'encoding';
Other features include:
Latin1 support more 8 bit cleaness
See doc/README.mb for more details. Note that the pacthes are
against May 30 snapshot.
Tatsuo Ishii
yyerror ones from bison. It also includes a few 'enhancements' to
the C programming style (which are, of course, personal).
The other patch removes the compilation of backend/lib/qsort.c, as
qsort() is a standard function in stdlib.h and can be used any
where else (and it is). It was only used in
backend/optimizer/geqo/geqo_pool.c, backend/optimizer/path/predmig.c,
and backend/storage/page/bufpage.c
> > Some or all of these changes might not be appropriate for v6.3,
since we > > are in beta testing and since they do not affect the
current functionality. > > For those cases, how about submitting
patches based on the final v6.3 > > release?
There's more to come. Please review these patches. I ran the
regression tests and they only failed where this was expected
(random, geo, etc).
Cheers,
Jeroen
Tom Lane
Peter Eisentraut
Bruce Momjian
Vadim B. Mikheev
Marc G. Fournier
Thomas G. Lockhart