the long-term plan for this behavior for quite some time, but it is only
possible now that DELETE has a USING clause so that the user can join
other tables in a DELETE statement without relying on this behavior.
and history files as per recent discussion. While at it, remove
pg_terminate_backend, since we have decided we do not have time during
this release cycle to address the reliability concerns it creates.
Split the 'Miscellaneous Functions' documentation section into
'System Information Functions' and 'System Administration Functions',
which hopefully will draw the eyes of those looking for such things.
heuristic determination of day vs month in date/time input. Add the
ability to specify that input is interpreted as yy-mm-dd order (which
formerly worked, but only for yy greater than 31). DateStyle's input
component now has the preferred spellings DMY, MDY, or YMD; the older
keywords European and US are now aliases for the first two of these.
Per recent discussions on pgsql-general.
only remnant of this failed experiment is that the server will take
SET AUTOCOMMIT TO ON. Still TODO: provide some client-side autocommit
logic in libpq.
initial values and runtime changes in selected parameters. This gets
rid of the need for an initial 'select pg_client_encoding()' query in
libpq, bringing us back to one message transmitted in each direction
for a standard connection startup. To allow server version to be sent
using the same GUC mechanism that handles other parameters, invent the
concept of a never-settable GUC parameter: you can 'show server_version'
but it's not settable by any GUC input source. Create 'lc_collate' and
'lc_ctype' never-settable parameters so that people can find out these
settings without need for pg_controldata. (These side ideas were all
discussed some time ago in pgsql-hackers, but not yet implemented.)
including:
- replacing all the appropriate usages of <citetitle>PostgreSQL
...</citetitle> with &cite-user;, &cite-admin;, and so on
- fix an omission in the EXECUTE documentation
- add some more text to the EXPLAIN documentation
- improve the PL/PgSQL RETURN NEXT documentation (more work to do here)
- minor markup fixes
Neil Conway
GUC support. It's now possible to set datestyle, timezone, and
client_encoding from postgresql.conf and per-database or per-user
settings. Also, implement rollback of SET commands that occur in a
transaction that later fails. Create a SET LOCAL var = value syntax
that sets the variable only for the duration of the current transaction.
All per previous discussions in pghackers.
reference page to new configuration system. Big update to administrator's
guide, chapters Runtime environment, Client authentication, and User
management, the latter two were part of the old Security chapter.
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.
Neil Conway
Tom Lane
PostgreSQL Daemon
Peter Eisentraut
Bruce Momjian
Thomas G. Lockhart
Tatsuo Ishii