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><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="RELEASE-8-5"
>E.1. Release 8.5alpha3</A
></H1
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="AEN95975"
>E.1.1. Overview</A
></H2
><P
> PostgreSQL alpha releases are snapshots of development code. They
are intended to preview and test upcoming features and to provide
the possibility for early feedback. They should not be used in
production installations or active development projects. While the
PostgreSQL code is continuously subject to a number of automated
and manual tests, alpha releases might have serious bugs. Also
features may be changed incompatibly or removed at any time during
the development cycle.
</P
><P
> The development cycle of a PostgreSQL major release alternates
between periods of development and periods of integration work,
called commit fests, normally one month each. Alpha releases are
planned to be produced at the end of every commit fest, thus every
two months. Since the first commit fest starts within a month from
the beginning of development altogether, early alpha releases are
not indicative of the likely feature set of the final release.
</P
><P
> The release notes below highlight user visible changes and new
features. There are normally numerous bug fixes and performance
improvements in every new snapshot of PostgreSQL, and it would be
too bulky to attempt to list them all. Note that many bug fixes are
also backported to stable releases of PostgreSQL, and you should be
using those if you are looking for bug-fix-only upgrades for your
current installations.
</P
><P
> The release notes are cumulative over all alpha releases. Items
that are new in the latest alpha release
are <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>emphasized</I
></SPAN
>.
</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="AEN95982"
>E.1.2. Migration</A
></H2
><P
> To upgrade from any release to an alpha release or from an alpha
release to any other release will most likely require a
dump/restore upgrade procedure. It may happen that this is not
necessary in particular cases, but that is not verified beforehand.
(The server will warn you in any case when a dump/restore is
necessary if you attempt to use it with an old data directory.)
Note, however, that the dump/restore upgrade procedure is expected
to work for alpha releases, and problems in this area should be
reported.
</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="AEN95985"
>E.1.3. Testing</A
></H2
><P
> The primary reason we release alphas is to get users to test new
features as early as possible. If you are interested in helping
with organized testing, please see
<A
HREF="http://wiki.postgresql.org/wiki/HowToBetaTest"
TARGET="_top"
>the
testing information page</A
>.
</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="AEN95989"
>E.1.4. Changes</A
></H2
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN95991"
>E.1.4.1. SQL Features</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Remove previously deprecated configuration
parameter add_missing_from. The system now always behaves as
though add_missing_from were off.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Performance and behavioral improvements in UPDATE,
DELETE, and SELECT FOR UPDATE/SHARE queries with joins.
Fix various corner cases that could have resulted in duplicated output
rows. Set-returning functions are now prohibited in the
target list of SELECT FOR UPDATE/SHARE. FOR UPDATE does not
propagate into a WITH query anymore.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Fix SELECT FOR UPDATE/SHARE in conjunction with LIMIT.
Previously, it could return fewer rows than the limit specified.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add a WHEN clause to CREATE TRIGGER, allowing a boolean expression
to be checked to determine whether the trigger should be fired.</I
></SPAN
>
</P
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>For BEFORE triggers this is mostly a matter of spec compliance; but
for AFTER triggers it can provide a noticeable performance
improvement, since queuing of a deferred trigger event and
re-fetching of the row(s) at end of statement can be
short-circuited if the trigger does not need to be fired.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add exclusion constraints, which generalize the concept of
uniqueness to support any indexable commutative operator, not just
equality. Two rows violate the exclusion constraint if
"row1.col OP row2.col" is TRUE for each of the columns in
the constraint.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Support ORDER BY within aggregate function calls, at long last
providing a non-kluge method for controlling the order in which
values are fed to an aggregate function. At the same time eliminate
the old implementation restriction that DISTINCT was only supported
for single-argument aggregates.</I
></SPAN
>
</P
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Behavioral change: formerly, agg(DISTINCT x) dropped null values of
x unconditionally. Now, it does so only if the aggregate's transition
function is strict; otherwise nulls are treated as DISTINCT
normally would, i.e., you get one copy.</I
></SPAN
>
</P
></LI
><LI
><P
> Add SQL-compliant triggers on columns, which fire only if
certain columns are named in the UPDATE's SET list.
</P
></LI
><LI
><P
> Add CREATE LIKE INCLUDING COMMENTS and STORAGE, and INCLUDING
ALL shortcut to allow users to make an exact copy of a table including
all options and features.
</P
></LI
><LI
><P
> Define a new, more extensible syntax for COPY options
in order to support additional COPY options in the future.
</P
></LI
><LI
><P
> Modify the definition of window-function PARTITION
BY and ORDER BY clauses so that their elements are always
taken as simple expressions over the query's input
columns. This fixes a bug.
</P
></LI
><LI
><P
> Fix bug with nested WITH RECURSIVE statements.
</P
></LI
><LI
><P
> Add surrogate pair support for U& string and identifier
syntax.
</P
></LI
><LI
><P
> Add Unicode escapes in E'...' strings.
</P
></LI
><LI
><P
> DROP COLUMN and DROP CONSTRAINT now support an IF EXISTS clause so
that users can avoid fatal errors when running repeatable scripts.
</P
></LI
><LI
><P
> UNIQUE constraints can now be DEFERRABLE. This is primarily useful
for incremental updates of numerical keys, e.g. "ID = ID +
1"
</P
></LI
><LI
><P
> Allow parentheses around the query expression that follows a WITH
clause.
</P
></LI
><LI
><P
> INFORMATION_SCHEMA, a catalog of standard views of database
objects, has been updated to the SQL:2008 standard.
</P
></LI
><LI
><P
> Change character_octet_length to more sensible values in
INFORMATION_SCHEMA.
</P
></LI
><LI
><P
> Allow * as parameter for FORCE QUOTE for COPY CSV, so that all
columns will be quoted.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96042"
>E.1.4.2. Performance</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Allow rewriting forms of ALTER TABLE to skip WAL
logging.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Speed up INFORMATION_SCHEMA's privilege views.</I
></SPAN
>
</P
></LI
><LI
><P
> Make TRUNCATE do truncate-in-place when processing
a relation that was created or previously truncated in the
current (sub)transaction.
</P
></LI
><LI
><P
> Implement "join removal" for cases where the inner side
of a left join is unique and is not referenced above the join. This should
speed up many ORM-generated and reporting tool queries.
</P
></LI
><LI
><P
> Remove the use of the flat files pg_auth and
pg_database in order to improve performance. (Warning: pgbouncer
and possibly other tools currently suggest referring to the pg_auth
file for its user database. Such schemes will no longer work.)
</P
></LI
><LI
><P
> EXPLAIN allows output of plans in XML, JSON, or YAML format for automated
processing of explain plans by analysis or visualization tools.
</P
></LI
><LI
><P
> EXPLAIN now supports the use of generic options in EXPLAIN ( option
value, ... ) format, which permits the creation of additional
EXPLAIN options.
</P
></LI
><LI
><P
> ALTER TABLE ... ALTER COLUMN ... SET STATISTICS DISTINCT allows
users to manually tweak the number of distinct values estimated for
a column, to fix cases where ANALYZE estimates are incorrect.
</P
></LI
><LI
><P
> Make GEQO's planning deterministic by having it start from a
predictable random number seed each time.
</P
></LI
><LI
><P
> Rewrite GEQO's gimme_tree function so that it always finds a legal
join sequence. Previously, it could have failed to produce a plan
in some cases.
</P
></LI
><LI
><P
> Tweak TOAST code so that columns marked with MAIN storage strategy
are not forced out-of-line unless that is necessary to make the row
fit on a page. Previously, they were forced out-of-line if needed
to get the row down to the default target size (1/4th page).
</P
></LI
><LI
><P
> Simplify the forms foo <> true and foo <> false to foo
= false and foo = true during query optimization.
</P
></LI
><LI
><P
> Avoid per-send() system calls to manage SIGPIPE in libpq, if the
platform provides either sockopt(SO_NOSIGPIPE) or the MSG_NOSIGNAL
flag to send().
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96073"
>E.1.4.3. Administration and Monitoring</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Allow read-only connections during recovery, also
known as Hot Standby. This provides a built-in master-slave
replication solution.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Provide a parenthesized-options syntax for VACUUM, analogous to
that recently adopted for EXPLAIN. This will allow additional
options to be implemented in future without having to make them
fully-reserved keywords. The old syntax remains available for
existing options, however.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add support for an application_name parameter, which is displayed
in pg_stat_activity and recorded in log entries.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Fix longstanding problems in VACUUM caused by untimely
interruptions.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add YAML to list of EXPLAIN formats.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add an EXPLAIN (BUFFERS) option to show buffer-usage statistics.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add a hook to let loadable modules get control at ProcessUtility
execution, and use it to extend contrib/pg_stat_statements to track
utility commands.</I
></SPAN
>
</P
></LI
><LI
><P
> Add a Boolean server configuration parameter
"bonjour" to control whether a Bonjour-enabled
build actually attempts to advertise itself via Bonjour.
</P
></LI
><LI
><P
> When reloading postgresql.conf, log what parameters actually
changed.
</P
></LI
><LI
><P
> Make it possibly to specify server configuration parameters
per user-database combination. Add a \drds command to psql to
display the settings.
</P
></LI
><LI
><P
> Allow the collection of statistics on sequences.
</P
></LI
><LI
><P
> Increase the maximum value of extra_float_digits to
3, and have pg_dump use that value when the backend is new
enough to allow it, because it is possible to need 3 extra
digits for float4 values (but not for float8 values).
</P
></LI
><LI
><P
> Add the ability to include the SQLSTATE error code of any error
messages in the PostgreSQL activity log with the new
log_line_prefix placeholder %e.
</P
></LI
><LI
><P
> Show the exact value being complained of in
unique-constraint-violation error messages, including unique-index
build failures.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96111"
>E.1.4.4. Security</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>When querying a table with child tables, do not check permissions
on the child tables, only on the parent table. The old behavior was
found to be useless and confusing in virtually all cases, and also
contrary to the SQL standard.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add a hook to CREATE/ALTER ROLE to allow an external module to
check the strength of database passwords, and create a sample
implementation of such a hook as a new contrib module
"passwordcheck".</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add large object access control.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Allow LDAP authentication to operate in search+bind
mode, meaning it does a search for the user in the directory
first, and then binds with the DN found for this user. This
allows for LDAP logins in scenarios where the DN of the user
cannot be determined simply by prefix and suffix, such as the
case where different users are located in different
containers. The old way of authentication can be
significantly faster, so it's kept as an option.</I
></SPAN
>
</P
></LI
><LI
><P
> Add ALTER DEFAULT PRIVILEGES command, which allows
users to adjust the privileges that will be applied to
subsequently-created objects.
</P
></LI
><LI
><P
> Add GRANT/REVOKE ON ALL TABLES/SEQUENCES/FUNCTIONS IN SCHEMA.
This makes it easier to manage permissions on database objects.
</P
></LI
><LI
><P
> Support "samehost" and "samenet" specifications
in pg_hba.conf. This allows users with dynamic server addresses to run
PostgreSQL without frequently modifying pg_hba.conf.
</P
></LI
><LI
><P
> New has_sequence_privilege() functions allow you to check sequence
privileges for a given ROLE.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96134"
>E.1.4.5. Built-In Functions</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Remove configuration parameter regex_flavor. It is now always
"advanced".</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Teach the regular expression functions to do case-insensitive
matching and locale-dependent character classification properly
when the database encoding is UTF8. This previously only worked
correctly for single-byte encodings. It is still broken for other
multibyte encodings.</I
></SPAN
>
</P
></LI
><LI
><P
> Support POSIX-compatible interpretation of ? as well as {m,n}
and related constructs in SIMILAR TO, per SQL:2008.
</P
></LI
><LI
><P
> The to_char() formatting functions now supports EEEE (scientific
notation).
</P
></LI
><LI
><P
> Use floor() not rint() when reducing precision of fractional
seconds in timestamp_trunc, timestamptz_trunc, and interval_trunc()
for the float-datetime case. This improves accuracy of time
calculations.
</P
></LI
><LI
><P
> Fix ancient bug in handling of to_char() modifier 'TH', when used
with HH.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96151"
>E.1.4.6. Data Types</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>When doing "ARRAY[...]::domain", where domain is a domain
over an array type, we need to check domain constraints. Regression
introduced in 8.4.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Fix integer-to-bit-string conversions to handle the first
fractional byte correctly when the output bit width is wider than
the given integer by something other than a multiple of 8 bits.</I
></SPAN
>
</P
></LI
><LI
><P
> Fix encoding handling in binary input function of xml type.
</P
></LI
><LI
><P
> Tighten binary receive functions so that they reject values
that the text input functions don't accept either.
</P
></LI
><LI
><P
> New hex-string input and output format options for type bytea. Hex
output format is enabled by default, which is an incompatible
change. See the new bytea_output parameter if you need to restore
compatibility.
</P
></LI
><LI
><P
> Adds prefix support for text search synonym dictionary, allowing
creation of synonyms on partial matches.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96168"
>E.1.4.7. Server Tools</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>initdb now selects the encoding SQL_ASCII when the locale specifies
US-ASCII. This case previously failed.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add init[db] option to pg_ctl.</I
></SPAN
>
</P
></LI
><LI
><P
> It is now reasonably safe to use pg_ctl to start
the postmaster from a boot-time script.
</P
></LI
><LI
><P
> pg_dump/pg_restore --clean now drops large objects.
</P
></LI
><LI
><P
> Modify parallel pg_restore ordering logic to avoid a potential
O(N^2) slowdown for some complex databases.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96183"
>E.1.4.8. libpq</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Throw error when a specified connection service name is not
found in pg_service.conf, instead of ignoring it.</I
></SPAN
>
</P
></LI
><LI
><P
> Make libpq reject non-numeric and out-of-range port numbers with a
suitable error message.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96191"
>E.1.4.9. psql</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>In psql, show view definition only with \d+, not with \d.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>In psql, ignore UTF-8-encoded Unicode byte-order mark at the
beginning of a file if the client encoding is UTF-8.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Improve psql's tabular display of wrapped-around data by inserting
markers in the formerly-always-blank columns just to left and right
of the data. "pset linestyle old-ascii" is added to make
the previous behavior available if anyone really wants it.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Simplify psql's new linestyle behavior to default to
linestyle=ascii all the time, rather than hoping we can tell
whether the terminal supports UTF-8 characters.</I
></SPAN
>
</P
></LI
><LI
><P
> Implement significantly saner behavior when two or
more psql sessions overlap in their use of the history file.
</P
></LI
><LI
><P
> Add "pset linestyle ascii/unicode" option to psql,
allowing our traditional ASCII-art style of table output to
be upgraded to use Unicode box drawing characters if
desired.
</P
></LI
><LI
><P
> Have \d show child tables that inherit from the specified parent
</P
></LI
><LI
><P
> psql now shows the index methods in \di
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96214"
>E.1.4.10. Procedural Languages</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>PL/pgSQL is installed by default.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Remove PL/pgSQL's RENAME declaration, which has
bizarre and mostly nonfunctional behavior, and is so little
used that no one has been interested in fixing it. To ensure
that possible uses are covered, remove the ALIAS declaration's
arbitrary restriction that only $n identifiers can be
aliased.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>The PL/pgSQL parser and scanner were reworked to behave much more
sanely:</I
></SPAN
>
</P
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>A variable reference will only be recognized where it can validly
go, ie, a place where a column value or parameter would be legal,
instead of the former behavior that would replace any textual match
including table names and column aliases (leading to syntax errors
later on).</I
></SPAN
>
</P
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>When a name could refer either to a PL/pgSQL variable or a
table column, PL/pgSQL formerly always assumed the variable was
meant, sometimes resulting in surprising behavior. Now, PL/pgSQL
can assume the variable is meant, or assume the table column is
meant, or throw an error in ambiguous cases. For safety the default
is to throw error. To configure this see <A
HREF="plpgsql-implementation.html#PLPGSQL-VAR-SUBST"
>the PL/pgSQL documentation</A
>.</I
></SPAN
>
</P
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Error reporting is much nicer: it no longer shows edited
versions of statements that look significantly different from what
you wrote.</I
></SPAN
>
</P
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Note that this change affects the set of keywords that are
reserved in PL/pgSQL (i.e., cannot be the name of a PL/pgSQL
variable). Now, all keywords shown as reserved in <A
HREF="sql-keywords-appendix.html"
>Appendix C</A
> are reserved for
PL/pgSQL purposes as well. However, many PL/pgSQL-only keywords
that were formerly treated as reserved no longer are. As in regular
SQL, you can double-quote a variable's name if you want to use a
name that conflicts with a reserved keyword.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add support for anonymous code blocks (DO blocks) to PL/Perl.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Support arrays as parameters and return values of PL/Python
functions.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add Python 3 support to PL/Python. It behaves more or less
unchanged compared to Python 2, but the new language variant is
called plpython3u.</I
></SPAN
>
</P
></LI
><LI
><P
> Add DO statement to support execution of procedural language
code without having to create a function for it.
</P
></LI
><LI
><P
> Support use of function argument names to identify which
actual arguments match which function parameters. The syntax
uses AS, for example funcname(value AS arg1, anothervalue AS
arg2).
</P
></LI
><LI
><P
> Fix/improve bytea and boolean support in PL/Python. Data type
conversion into and out of PL/Python previously went through
an intermediate string representation, which caused various
discrepancies especially with bytea and boolean data. This is
now fixed by converting the values directly.
</P
></LI
><LI
><P
> PL/Python now accepts Unicode objects where it previously
only accepted string objects (for example, as return
value). Unicode objects are converted to the PostgreSQL
server encoding as necessary.
</P
></LI
><LI
><P
> Improve error context reporting in PL/Perl, for
easier debugging.
</P
></LI
><LI
><P
> PL/pgSQL IN parameters now accept value assignments.
</P
></LI
><LI
><P
> Convert a Perl array to a PostgreSQL array when returned by
set-returning functions as well as non-SRFs.
</P
></LI
><LI
><P
> Allow cursor commands MOVE FORWARD n, MOVE BACKWARD n,
MOVE FORWARD ALL, MOVE BACKWARD ALL in PL/pgSQL.
</P
></LI
><LI
><P
> PL/pgSQL functions can now better cope with row types
containing dropped columns.
</P
></LI
><LI
><P
> Improve error context reporting in PL/Python, for easier
debugging.
</P
></LI
><LI
><P
> Greatly expand the regression testing for PL/Python.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96267"
>E.1.4.11. Additional Supplied Modules</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Add \shell and \setshell meta commands to pgbench.</I
></SPAN
>
</P
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>\shell runs an external shell command. \setshell
does the same and assigns the result to a variable.</I
></SPAN
>
</P
></LI
><LI
><P
> Multiple improvements in contrib/hstore, including
raising limits on keys and values, conversions to and from
records and arrays, and support for GROUP BY and DISTINCT.
</P
></LI
><LI
><P
> pgbench is now multi-threaded, allowing it to use multiple CPU's
for its client connections, and to do more realistic workload
testing.
</P
></LI
><LI
><P
> Added the ability to retrieve asynchronous notifications using
dblink, via the addition of the function dblink_get_notify().
</P
></LI
><LI
><P
> Added matchorig, matchsynonyms, and keepsynonyms options to
contrib/dict_xsyn.
</P
></LI
><LI
><P
> Added contrib/unaccent.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96285"
>E.1.4.12. ecpg</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Refactor ECPG grammar so that it uses the core grammar's
unreserved_keyword list, minus a few specific words that have to be
treated specially. This de-reserves a number of words in ECPG.</I
></SPAN
>
</P
></LI
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Added dynamic cursor names to ECPG.</I
></SPAN
>
</P
></LI
><LI
><P
> Add ECPG function that returns the current transaction status.
</P
></LI
><LI
><P
> Make ECPG more robust against applications freeing strings.
</P
></LI
><LI
><P
> ECPG now includes a STRING datatype for Informix compatibility
mode.
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96300"
>E.1.4.13. Ports</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>Disable triggering failover with a signal in pg_standby on Windows.
It never really worked before anyway.</I
></SPAN
>
</P
></LI
><LI
><P
> Change the WIN32 API version to be 5.01 (Windows XP), to
bring in the proper IPv6 headers in newer SDKs.
</P
></LI
><LI
><P
> Write to the Windows eventlog in UTF-16, converting the
message encoding as necessary.
</P
></LI
><LI
><P
> Replace use of the long-deprecated Bonjour API
DNSServiceRegistrationCreate with the not-so-deprecated
DNSServiceRegister. The new code will fail on Mac OS X
releases before 10.3.
</P
></LI
><LI
><P
> Reserve the shared memory region during backend startup on Windows,
so that memory allocated by starting third party DLLs doesn't end
up conflicting with it. Hopefully this solves the long-time issue
with "could not reattach to shared memory" errors on
Win32.
</P
></LI
><LI
><P
> Add s_lock support for SuperH architecture (not well tested).
</P
></LI
></UL
></DIV
><DIV
CLASS="SECT3"
><H3
CLASS="SECT3"
><A
NAME="AEN96316"
>E.1.4.14. Source Code, Build Options</A
></H3
><P
></P
><UL
><LI
><P
> <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>configure --enable-thread-safety is now the default (but can still
be turned off).</I
></SPAN
>
</P
></LI
><LI
><P
> Fix inclusions of readline/editline header files so that we
only attempt to #include the version of history.h that is in
the same directory as the readline.h we are using. This
avoids problems in some scenarios where both readline and
editline are installed.
</P
></LI
><LI
><P
> Derived files that are shipped in the distribution used to be
built in the source directory even for out-of-tree
builds. They are now built in the build tree. This
should be more convenient for certain developers' workflows.
</P
></LI
><LI
><P
> Functions which conflict with C++ reserved words have been renamed,
making backend header files now safe to use with C++ libraries.
</P
></LI
><LI
><P
> Add man pages for SPI functions.
</P
></LI
><LI
><P
> Upgrade to Autoconf 2.63 (not relevant to users of distribution
tarballs).
</P
></LI
><LI
><P
> Minimum version of Flex is now 2.5.31, to support reentrant
scanners (not relevant to users of distribution tarballs).
</P
></LI
><LI
><P
> Documentation build rules have been improved. The generated
documentation files are now shipped "loose", not in
sub-tarballs.
</P
></LI
><LI
><P
> New toolchain to generate man pages. From now on, the man pages
will be current in every release.
</P
></LI
><LI
><P
> Code-coverage testing support now extends to the entire source
tree, not only src/backend/.
</P
></LI
><LI
><P
> Make the core scanner re-entrant, along with additional fixes that
will let it be used directly by PL/pgSQL.
</P
></LI
></UL
></DIV
></DIV
></DIV
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