is a large enough histogram, it will use the number of matches in the
histogram to derive a selectivity estimate, rather than the admittedly
pretty bogus heuristics involving examining the pattern contents. I set
'large enough' at 100, but perhaps we should change that later. Also
apply the same technique in contrib/ltree's <@ and @> estimator. Per
discussion with Stefan Kaltenbrunner and Matteo Beccati.
Stark, additional fixes and editorialization by Neil Conway. Greg's patch
description:
Some more doc patches for partitioned tables. In particular replace
the caveat that INCLUDING CONSTRAINTS doesn't exist and replace it
with documentation of, well, INCLUDING CONSTRAINTS.
Also, there was an instance of "LIKE WITH DEFAULTS" which is
actually spelled "LIKE INCLUDING DEFAULTS".
tables in the query compete for cache space, not just the one we are
currently costing an indexscan for. This seems more realistic, and it
definitely will help in examples recently exhibited by Stefan
Kaltenbrunner. To get the total size of all the tables involved, we must
tweak the handling of 'append relations' a bit --- formerly we looked up
information about the child tables on-the-fly during set_append_rel_pathlist,
but it needs to be done before we start doing any cost estimation, so
push it into the add_base_rels_to_query scan.
< #A hyphen, "-", marks changes that will appear in the upcoming 8.2 release.#
> #A hyphen, "-", marks changes that will appear in the upcoming 8.3 release.#
< * -Make postmater and postgres options distinct so the postmaster -o
< option is no longer needed
< * -Allow pooled connections to list all prepared statements
<
< This would allow an application inheriting a pooled connection to know
< the statements prepared in the current session.
<
< * -Re-enable the GUC full_page_writes in 8.2 when reliability issues have
< been addressed
< o -Add "include file" functionality in postgresql.conf
< o -Allow per-database permissions to be set via GRANT
<
< Allow database connection checks based on GRANT rules in
< addition to the existing access checks in pg_hba.conf.
<
< o -Issue a warning if a change-on-restart-only postgresql.conf value
> o Issue a warning if a change-on-restart-only postgresql.conf value
< o -Automatically force archiving of partially-filled WAL files when
< pg_stop_backup() is called or the server is stopped
< o -Add reporting of the current WAL file and offset, perhaps as
< part of partial log file archiving
< * -Allow server logs to be remotely read and removed using SQL commands
< * -Allow protocol-level BIND parameter values to be logged
< * -Zero umasked bits in conversion from INET cast to CIDR
< * -Prevent INET cast to CIDR from dropping netmask, SELECT '1.1.1.1'::inet::cidr
< * -Allow INET + INT8 to increment the host part of the address or
< throw an error on overflow
< * -Add 'tid != tid ' operator for use in corruption recovery
< o -Allow customization of the known set of TZ names (generalize the
< present australian_timezones hack)
< o -Allow timezone names in SQL strings, '2006-05-24 21:11
< Americas/New_York'::timestamptz
< o -Add support for day-time syntax, INTERVAL '1 2:03:04' DAY TO
< SECOND
< o -Allow NULLs in arrays
< * -Add transaction_timestamp(), statement_timestamp(), clock_timestamp()
< functionality
<
< Current CURRENT_TIMESTAMP returns the start time of the current
< transaction, and gettimeofday() returns the wallclock time. This will
< make time reporting more consistent and will allow reporting of
< the statement start time.
<
< * -Allow to_char() to print localized month names
< * -Add sleep() function, remove from regress.c
< * -Allow user-defined functions retuning a domain value to enforce domain
< constraints
< * -Allow TRUNCATE ... CASCADE/RESTRICT
<
< This is like DELETE CASCADE, but truncates.
<
< * -Add COMMENT ON for all cluster global objects (roles, databases
< and tablespaces)
< * -Make row-wise comparisons work per SQL spec
<
< Right now, '(a, b) < (1, 2)' is processed as 'a < 1 and b < 2', but
< the SQL standard requires it to be processed as a column-by-column
< comparison, so the proper comparison is '(a < 1) OR (a = 1 AND b < 2)'.
<
< * -Enable escape_string_warning and standard_conforming_strings
> * Enable standard_conforming_strings
< o -Add ON COMMIT capability to CREATE TABLE AS ... SELECT
< o -Allow an alias to be provided for the target table in
< UPDATE/DELETE (Neil)
< o -Allow UPDATE tab SET ROW (col, ...) = (val, ...) for updating
< multiple columns
< o -Add ALTER TABLE tab INHERIT / NO INHERIT parent
< o -Have COPY return the number of rows loaded/unloaded?
< o -Allow COPY (SELECT ...) TO 'filename'
<
< o -Allow pooled connections to list all open WITH HOLD cursors
<
< Because WITH HOLD cursors exist outside transactions, this allows
< them to be listed so they can be closed.
<
< o -Allow INSERT INTO tab (col1, ..) VALUES (val1, ..), (val2, ..)
< o -Allow INSERT/UPDATE ... RETURNING new.col or old.col
< o -Allow PL/python to return composite types and result sets
<
< * -Have initdb set the input DateStyle (MDY or DMY) based on locale
< o -Improve psql's handling of multi-line statements
<
< Currently, while \e saves a single statement as one entry, interactive
< statements are saved one line at a time. Ideally all statements
< would be saved like \e does.
<
< o -Allow multi-line column values to align in the proper columns
<
< If the second output column value is 'a\nb', the 'b' should appear
< in the second display column, rather than the first column as it
< does now.
<
< o -Display IN, INOUT, and OUT parameters in \df
< o -Allow pg_dump to use multiple -t and -n switches, exclusion
< ability, and regular expression object matching
< o -Update pg_dump and psql to use the new COPY libpq API (Christopher)
< o -Add a function to support Parse/DescribeStatement capability
< * -Add fillfactor to control reserved free space during index creation
< * -Add system view to show free space map contents
< * -Allow installing to directories containing spaces
<
< This is possible if proper quoting is added to the makefiles for the
< install targets. Because PostgreSQL supports relocatable installs, it
< is already possible to install into a directory that doesn't contain
< spaces and then copy the install to a directory with spaces.
<
< * -%Clean up compiler warnings (especially with gcc version 4)
< * -Remove BeOS and QNX-specific code
< o -Port contrib/xml2
an SQL dump if an error occurs. Along the way, make some improvements and
copy-edits to the surrounding text. Patch from Simon Riggs, additional
fixes by Neil Conway.
contrib functionality. Along the way, remove the USER_LOCKS configuration
symbol, since it no longer makes any sense to try to compile that out.
No user documentation yet ... mmoncure has promised to write some.
Thanks to Abhijit Menon-Sen for creating a first draft to work from.
>
> * Set client encoding based on the client operating system encoding
>
> Currently client_encoding is set in postgresql.conf, which
> defaults to the server encoding.
oversight in original implementation of VALUES. Also fix an oversight
in recent addition of options to CREATE TABLE AS: they weren't getting
propagated if the query was a set-operation such as UNION.
the table being analyzed. This prevents two ANALYZEs from running
concurrently on the same table and possibly suffering concurrent-update
failures while trying to store their results into pg_statistic. The
downside is that a database-wide ANALYZE executed within a transaction
block will hold ShareUpdateExclusiveLock on many tables simultaneously,
which could lead to concurrency issues or even deadlock against another
such ANALYZE. However, this seems a corner case of less importance
than getting unexpected errors from a foreground ANALYZE when autovacuum
elects to analyze the same table concurrently. Per discussion.
after an error during VACUUM. We have a PG_TRY block anyway around the only
call sites, so just reset it in the CATCH clause instead of having
AtEOXact_Buffers blindly do it during xact end. I think the old code was
actively wrong for the case of a failure during ANALYZE inside a
subtransaction --- the flag wouldn't get cleared until main transaction end.
Probably not worth back-patching though.
< o Reorder physical storage order to reduce padding?
<
< This involves having the user-specified order of columns
< be different from the physical order. SELECT * would
< need to reorder the physical values to match the
< user-specified ordering.
<
< o Store disk pages with no alignment/padding?
<
< This necessitates adding CPU-required padding when moving
< rows from disk to memory.
<
< One idea is to store the header in network byte order (high bits
< first), and read the high bits to determine the header length.
< http://archives.postgresql.org/pgsql-hackers/2006-09/msg00848.php
> One idea is to create zero-or-one-byte-header versions
> of varlena data types. In involves setting the high-bit and
> 0-127 length in the single-byte header, or clear the high bit
> and store the 7-bit ASCII value in the rest of the byte.
> The small-header versions have no alignment requirements.
> http://archives.postgresql.org/pgsql-hackers/2006-09/msg01372.php
and create a new view pg_timezone_names that provides information about
the zones known in the 'zic' database. Magnus Hagander, with some
additional work by Tom Lane.
alias with the old name for backwards compatibility. Per discussion,
the old name is actively wrong because validity and well-formedness
have different meanings in XML.
Teodor Sigaev