how often we do SSL session key renegotiation. Can be set to
0 to disable renegotiation completely, which is required if
a broken SSL library is used (broken patches to CVE-2009-3555
a known cause) or when using a client library that can't do
renegotiation.
This operates in the same way as other CREATE OR REPLACE commands, ie,
it replaces everything but the ownership and ACL lists of an existing
entry, and requires the caller to have owner privileges for that entry.
While modifying an existing language has some use in development scenarios,
in typical usage all the "replaced" values come from pg_pltemplate so there
will be no actual change in the language definition. The reason for adding
this is mainly to allow programs to ensure that a language exists without
triggering an error if it already does exist.
This commit just adds and documents the new option. A followon patch
will use it to clean up some unpleasant cases in pg_dump and pg_regress.
In addition, add support for a "payload" string to be passed along with
each notify event.
This implementation should be significantly more efficient than the old one,
and is also more compatible with Hot Standby usage. There is not yet any
facility for HS slaves to receive notifications generated on the master,
although such a thing is possible in future.
Joachim Wieland, reviewed by Jeff Davis; also hacked on by me.
This patch allows the frame to start from CURRENT ROW (in either RANGE or
ROWS mode), and it also adds support for ROWS n PRECEDING and ROWS n FOLLOWING
start and end points. (RANGE value PRECEDING/FOLLOWING isn't there yet ---
the grammar works, but that's all.)
Hitoshi Harada, reviewed by Pavel Stehule
sections under "High Availability, Load Balancing, and Replication"
chapter. Streaming replication chapter needs a lot more work, but this
commit just moves things around.
being called as aggregates, and to get the aggregate transition state memory
context if needed. Use it instead of poking directly into AggState and
WindowAggState in places that shouldn't know so much.
We should have done this in 8.4, probably, but better late than never.
Revised version of a patch by Hitoshi Harada.
VACUUM FULL INPLACE), along with a boatload of subsidiary code and complexity.
Per discussion, the use case for this method of vacuuming is no longer large
enough to justify maintaining it; not to mention that we don't wish to invest
the work that would be needed to make it play nicely with Hot Standby.
Aside from the code directly related to old-style VACUUM FULL, this commit
removes support for certain WAL record types that could only be generated
within VACUUM FULL, redirect-pointer removal in heap_page_prune, and
nontransactional generation of cache invalidation sinval messages (the last
being the sticking point for Hot Standby).
We still have to retain all code that copes with finding HEAP_MOVED_OFF and
HEAP_MOVED_IN flag bits on existing tuples. This can't be removed as long
as we want to support in-place update from pre-9.0 databases.
of shared or nailed system catalogs. This has two key benefits:
* The new CLUSTER-based VACUUM FULL can be applied safely to all catalogs.
* We no longer have to use an unsafe reindex-in-place approach for reindexing
shared catalogs.
CLUSTER on nailed catalogs now works too, although I left it disabled on
shared catalogs because the resulting pg_index.indisclustered update would
only be visible in one database.
Since reindexing shared system catalogs is now fully transactional and
crash-safe, the former special cases in REINDEX behavior have been removed;
shared catalogs are treated the same as non-shared.
This commit does not do anything about the recently-discussed problem of
deadlocks between VACUUM FULL/CLUSTER on a system catalog and other
concurrent queries; will address that in a separate patch. As a stopgap,
parallel_schedule has been tweaked to run vacuum.sql by itself, to avoid
such failures during the regression tests.
If expand_dbname is non-zero and dbname contains an = sign, it is taken as
a conninfo string in exactly the same way as if it had been passed to
PQconnectdb. This is equivalent to the way PQsetdbLogin() works, allowing
PQconnectdbParams() to be a complete alternative.
Also improve the way the new function is called from psql and replace a
previously missed call to PQsetdbLogin() in psql. Additionally use
PQconnectdbParams() for pg_dump and friends, and the bin/scripts
command line utilities such as vacuumdb, createdb, etc.
Finally, update the documentation for the new parameter, as well as the
nuances of precedence in cases where key words are repeated or duplicated
in the conninfo string.
the input values into a string. The two argument version also does the same
thing, but inserts delimiters between elements.
Original patch by Pavel Stehule, reviewed by David E. Wheeler and me.
false positives during Hot Standby conflict processing. Simple
patch to enhance conflict processing, following previous discussions.
Controlled by parameter minimize_standby_conflicts = on | off, with
default off allows measurement of performance impact to see whether
it should be set on all the time.
In addition to everything built installed and tested by all, install and installcheck targets, these build HTML Docs,
build and test contrib, and test PLs and ECPG.
PQconnectStartParams. These are analogous to PQconnectdb and PQconnectStart
respectively. They differ from the legacy functions in that they accept
two NULL-terminated arrays, keywords and values, rather than conninfo
strings. This avoids the need to build the conninfo string in cases
where it might be inconvenient to do so. Includes documentation.
Also modify psql to utilize PQconnectdbParams rather than PQsetdbLogin.
This allows the new config parameter application_name to be set, which
in turn is displayed in the pg_stat_activity view and included in CSV
log entries. This will also ensure both new functions get regularly
exercised.
Patch by Guillaume Lelarge with review and minor adjustments by
Joe Conway.
- Allow (ineffective) use of 'require' in plperl
If the required module is not already loaded then it dies.
So "use strict;" now works in plperl.
- Pre-load the feature module if perl >= 5.10.
So "use feature :5.10;" now works in plperl.
- Stored procedure subs are now given names.
The names are not visible in ordinary use, but they make
tools like Devel::NYTProf and Devel::Cover much more useful.
- Simplified and generalized the subroutine creation code.
Now one code path for generating sub source code, not four.
Can generate multiple 'use' statements with specific imports
(which handles plperl.use_strict currently and can easily
be extended to handle a plperl.use_feature=':5.12' in future).
- Disallows use of Safe version 2.20 which is broken for PL/Perl.
http://rt.perl.org/rt3/Ticket/Display.html?id=72068
- Assorted minor optimizations by pre-growing data structures.
Patch from Tim Bunce, reviewed by Alex Hunsaker.
default of "plpgsql". This is more reasonable than it was when the DO patch
was written, because we have since decided that plpgsql should be installed
by default. Per discussion, having a parameter for this doesn't seem useful
enough to justify the risk of application breakage if the value is changed
unexpectedly.
and implement OVERLAY() for bit strings and bytea.
In passing also convert text OVERLAY() to a true built-in, instead of
relying on a SQL function.
Leonardo F, reviewed by Kevin Grittner
woken by alarm we send SIGUSR1 to all backends requesting that they
check to see if they are blocking Startup process. If so, they throw
ERROR/FATAL as for other conflict resolutions. Deadlock stop gap
removed. max_standby_delay = -1 option removed to prevent deadlock.
Attributes can now have options, just as relations and tablespaces do, and
the reloptions code is used to parse, validate, and store them. For
simplicity and because these options are not performance critical, we store
them in a separate cache rather than the main relcache.
Thanks to Alex Hunsaker for the review.
PQescapeLiteral is similar to PQescapeStringConn, but it relieves the
caller of the need to know how large the output buffer should be, and
it provides the appropriate quoting (in addition to escaping special
characers within the string). PQescapeIdentifier provides similar
functionality for escaping identifiers.
Per recent discussion with Tom Lane.
quote_literal, quote_nullable, quote_ident,
encode_bytea, decode_bytea, looks_like_number,
encode_array_literal, encode_array_constructor.
Split SPI.xs into two - SPI.xs now contains only SPI functions. Remainder
are in new Util.xs.
Some more code and documentation cleanup along the way, as well as
adding some CVS markers to files missing them.
Original patch from Tim Bunce, with a little editing from me.
Modify the "Escaping Strings for Inclusion in SQL Commands" section
to use a <variablelist> as the preceding and following sections do,
and merge the "Escaping Binary Strings for Inclusion in SQL Commands"
section into it.
This changes only the formatting of these sections, not the content.
It is intended to lay the groundwork for a follow-on patch to add
some new escaping functions, but it makes sense to commit this first,
for clarity.
This is the last EXECUTE-like plpgsql statement that was missing
the capability of inserting parameter values via USING.
Pavel Stehule, reviewed by Itagaki Takahiro
pg_constraint before searching pg_trigger. This allows saner handling of
corner cases; in particular we now say "constraint is not deferrable"
rather than "constraint does not exist" when the command is applied to
a constraint that's inherently non-deferrable. Per a gripe several months
ago from hubert depesz lubaczewski.
To make this work without breaking user-defined constraint triggers,
we have to add entries for them to pg_constraint. However, in return
we can remove the pgconstrname column from pg_constraint, which represents
a fairly sizable space savings. I also replaced the tgisconstraint column
with tgisinternal; the old meaning of tgisconstraint can now be had by
testing for nonzero tgconstraint, while there is no other way to get
the old meaning of nonzero tgconstraint, namely that the trigger was
internally generated rather than being user-created.
In passing, fix an old misstatement in the docs and comments, namely that
pg_trigger.tgdeferrable is exactly redundant with pg_constraint.condeferrable.
Actually, we mark RI action triggers as nondeferrable even when they belong to
a nominally deferrable FK constraint. The SET CONSTRAINTS code now relies on
that instead of hard-coding a list of exception OIDs.
This includes two new kinds of postmaster processes, walsenders and
walreceiver. Walreceiver is responsible for connecting to the primary server
and streaming WAL to disk, while walsender runs in the primary server and
streams WAL from disk to the client.
Documentation still needs work, but the basics are there. We will probably
pull the replication section to a new chapter later on, as well as the
sections describing file-based replication. But let's do that as a separate
patch, so that it's easier to see what has been added/changed. This patch
also adds a new section to the chapter about FE/BE protocol, documenting the
protocol used by walsender/walreceivxer.
Bump catalog version because of two new functions,
pg_last_xlog_receive_location() and pg_last_xlog_replay_location(), for
monitoring the progress of replication.
Fujii Masao, with additional hacking by me
pginstaller isn't used anymore, in favor of the one-click installers.
Make it clear that we support Windows 2000 and newer with the native
port, instead of first saying we support NT4 and then saying we don't.
- Changed MULTIPLICITY check from runtime to compiletime.
No loads the large Config module.
- Changed plperl_init_interp() to return new interp
and not alter the global interp_state
- Moved plperl_safe_init() call into check_interp().
- Removed plperl_safe_init_done state variable
as interp_state now covers that role.
- Changed plperl_create_sub() to take a plperl_proc_desc argument.
- Simplified return value handling in plperl_create_sub.
- Changed perl.com link in the docs to perl.org and tweaked
wording to clarify that require, not use, is what's blocked.
- Moved perl code in large multi-line C string literal macros
out to plc_*.pl files.
- Added a test2macro.pl utility to convert the plc_*.pl files to
macros in a perlchunks.h file which is #included
- Simplifed plperl_safe_init() slightly
- Optimized pg_verifymbstr calls to avoid unneeded strlen()s.
Patch from Tim Bunce, with minor editing from me.
This uses the same infrastructure with EXPLAIN BUFFERS to support
{shared|local}_blks_{hit|read|written} andtemp_blks_{read|written}
columns in the pg_stat_statements view. The dumped file format
also updated.
Thanks to Robert Haas for the review.
VACUUM FULL was renamed to VACUUM FULL INPLACE. Also added a new
option -i, --inplace for vacuumdb to perform FULL INPLACE vacuuming.
Since the new VACUUM FULL uses CLUSTER infrastructure, we cannot
use it for system tables. VACUUM FULL for system tables always
fall back into VACUUM FULL INPLACE silently.
Itagaki Takahiro, reviewed by Jeff Davis and Simon Riggs.
This patch only supports seq_page_cost and random_page_cost as parameters,
but it provides the infrastructure to scalably support many more.
In particular, we may want to add support for effective_io_concurrency,
but I'm leaving that as future work for now.
Thanks to Tom Lane for design help and Alvaro Herrera for the review.
pg_attribute, by having genbki.pl derive the information from the various
catalog header files. This greatly simplifies modification of the
"bootstrapped" catalogs.
This patch finally kills genbki.sh and Gen_fmgrtab.sh; we now rely entirely on
Perl scripts for those build steps. To avoid creating a Perl build dependency
where there was not one before, the output files generated by these scripts
are now treated as distprep targets, ie, they will be built and shipped in
tarballs. But you will need a reasonably modern Perl (probably at least
5.6) if you want to build from a CVS pull.
The changes to the MSVC build process are untested, and may well break ---
we'll soon find out from the buildfarm.
John Naylor, based on ideas from Robert Haas and others
where to install DATA and DOCS files. This is mainly intended to allow
versioned installation, eg, install into contrib/fooM.N/ rather than
directly into contrib/.
Mark Cave-Ayland
to be just a minor extension of the previous patch that made "x IS NULL"
indexable, because we can treat the IS NOT NULL condition as if it were
"x < NULL" or "x > NULL" (depending on the index's NULLS FIRST/LAST option),
just like IS NULL is treated like "x = NULL". Aside from any possible
usefulness in its own right, this is an important improvement for
index-optimized MAX/MIN aggregates: it is now reliably possible to get
a column's min or max value cheaply, even when there are a lot of nulls
cluttering the interesting end of the index.
and teach ANALYZE to compute such stats for tables that have subclasses.
Per my proposal of yesterday.
autovacuum still needs to be taught about running ANALYZE on parent tables
when their subclasses change, but the feature is useful even without that.
choose an index name the same as it would do for an unnamed index constraint.
(My recent changes to the index naming logic have helped to ensure that this
will be a reasonable choice.) Per a suggestion from Peter.
A necessary side-effect is to promote CONCURRENTLY to type_func_name_keyword
status, ie, it can't be a table/column/index name anymore unless quoted.
This is not all bad, since we have heard more than once of people typing
CREATE INDEX CONCURRENTLY ON foo (...) and getting a normal index build of
an index named "concurrently", which was not what they wanted. Now this
syntax will result in a concurrent build of an index with system-chosen
name; which they can rename afterwards if they want something else.
CREATE FOREIGN DATA WRAPPER. Arguably it wasn't a bug because the
documentation said that it's passed the catalog ID or zero, but surely
we should provide it when it's known. And there isn't currently any
scenario where it's not known, and I can't imagine having one in the
future either, so better remove the "or zero" escape hatch and always
pass a valid catalog ID. Backpatch to 8.4.
Martin Pihlak
Enabled by recovery_connections = on (default) and forcing archive recovery using a recovery.conf. Recovery processing now emulates the original transactions as they are replayed, providing full locking and MVCC behaviour for read only queries. Recovery must enter consistent state before connections are allowed, so there is a delay, typically short, before connections succeed. Replay of recovering transactions can conflict and in some cases deadlock with queries during recovery; these result in query cancellation after max_standby_delay seconds have expired. Infrastructure changes have minor effects on normal running, though introduce four new types of WAL record.
New test mode "make standbycheck" allows regression tests of static command behaviour on a standby server while in recovery. Typical and extreme dynamic behaviours have been checked via code inspection and manual testing. Few port specific behaviours have been utilised, though primary testing has been on Linux only so far.
This commit is the basic patch. Additional changes will follow in this release to enhance some aspects of behaviour, notably improved handling of conflicts, deadlock detection and query cancellation. Changes to VACUUM FULL are also required.
Simon Riggs, with significant and lengthy review by Heikki Linnakangas, including streamlined redesign of snapshot creation and two-phase commit.
Important contributions from Florian Pflug, Mark Kirkwood, Merlin Moncure, Greg Stark, Gianni Ciolli, Gabriele Bartolini, Hannu Krosing, Robert Haas, Tatsuo Ishii, Hiroyuki Yamada plus support and feedback from many other community members.
Rewrite the documentation in more idiomatic English, and in the process make
it somewhat more succinct. Move the discussion of specific large object
privileges out of the "server-side functions" section, where it certainly
doesn't belong, and into "implementation features". That might not be
exactly right either, but it doesn't seem worth creating a new section for
this amount of information. Fix a few spelling and layout problems, too.
Behaves more or less unchanged compared to Python 2, but the new language
variant is called plpython3u. Documentation describing the naming scheme
is included.
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.
Possibly release-notable behavioral change: formerly, agg(DISTINCT x)
dropped null values of x unconditionally. Now, it does so only if the
agg transition function is strict; otherwise nulls are treated as DISTINCT
normally would, ie, you get one copy.
Andrew Gierth, reviewed by Hitoshi Harada
\shell command runs an external shell command.
\setshell also does the same and sets the result to a variable.
original patch by Michael Paquier with some editorialization by Itagaki,
and reviewed by Greg Smith.
This patch also removes buffer-usage statistics from the track_counts
output, since this (or the global server statistics) is deemed to be a better
interface to this information.
Itagaki Takahiro, reviewed by Euler Taveira de Oliveira.
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.
Robert Fleming and Magnus Hagander
pg_ctl gets a new mode that runs initdb. Adjust the documentation a bit to
not assume that initdb is the only way to run database cluster initialization.
But don't replace initdb as the canonical way.
Author: Zdenek Kotala <Zdenek.Kotala@Sun.COM>
git mirror.
Remove information about cvsup and documentation that's more about cvs
than our use of cvs.
Backpatch to 8.4 so we get the git information up on the website as
soon as possible.
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.
Jeff Davis, reviewed by Robert Haas
to the client by the server. This might seem pretty pointless but apparently
it will help pgbouncer, and perhaps other connection poolers. Anyway it's
practically free to do so for the normal use-case where appname is only set
in the startup packet --- we're just adding a few more bytes to the initial
ParameterStatus response packet. Per comments from Marko Kreen.
in the formerly-always-blank columns just to left and right of the data.
Different marking is used for a line break caused by a newline in the data
than for a straight wraparound. A newline break is signaled by a "+" in the
right margin column in ASCII mode, or a carriage return arrow in UNICODE mode.
Wraparound is signaled by a dot in the right margin as well as the following
left margin in ASCII mode, or an ellipsis symbol in the same places in UNICODE
mode. "\pset linestyle old-ascii" is added to make the previous behavior
available if anyone really wants it.
In passing, this commit also cleans up a few regression test files that
had unintended spacing differences from the current actual output.
Roger Leigh, reviewed by Gabrielle Roth and other members of PDXPUG.
checked to determine whether the trigger should be fired.
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.
Takahiro Itagaki, reviewed by KaiGai Kohei.
strength of database passwords, and create a sample implementation of
such a hook as a new contrib module "passwordcheck".
Laurenz Albe, reviewed by Takahiro Itagaki
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.
Itagaki Takahiro
default be "throw error on conflict", as per discussions. The GUC variable
is plpgsql.variable_conflict, with values "error", "use_variable",
"use_column". The behavior can also be specified per-function by inserting
one of
#variable_conflict error
#variable_conflict use_variable
#variable_conflict use_column
at the start of the function body.
The 8.5 release notes will need to mention using "use_variable" to retain
backward-compatible behavior, although we should encourage people to migrate
to the much less mistake-prone "error" setting.
Update the plpgsql documentation to match this and other recent changes.
it works just as well to have them be ordinary identifiers, and this gets rid
of a number of ugly special cases. Plus we aren't interfering with non-rule
usage of these names.
catversion bump because the names change internally in stored rules.
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.
(We could alternatively make RENAME act just like ALIAS, but per discussion
having two different ways to do the same thing is probably more confusing than
helpful.)
As proof of concept, modify plpgsql to use the hooks. plpgsql is still
inserting $n symbols textually, but the "back end" of the parsing process now
goes through the ParamRef hook instead of using a fixed parameter-type array,
and then execution only fetches actually-referenced parameters, using a hook
added to ParamListInfo.
Although there's a lot left to be done in plpgsql, this already cures the
"if (TG_OP = 'INSERT' and NEW.foo ...)" problem, as illustrated by the
changed regression test.
underneath the Limit node, not atop it. This fixes the old problem that such
a query might unexpectedly return fewer rows than the LIMIT says, due to
LockRows discarding updated rows.
There is a related problem that LockRows might destroy the sort ordering
produced by earlier steps; but fixing that by pushing LockRows below Sort
would create serious performance problems that are unjustified in many
real-world applications, as well as potential deadlock problems from locking
many more rows than expected. Instead, keep the present semantics of applying
FOR UPDATE after ORDER BY within a single query level; but allow the user to
specify the other way by writing FOR UPDATE in a sub-select. To make that
work, track whether FOR UPDATE appeared explicitly in sub-selects or got
pushed down from the parent, and don't flatten a sub-select that contained an
explicit FOR UPDATE.
for example in
WITH w AS (SELECT * FROM foo) SELECT * FROM w, bar ... FOR UPDATE
the FOR UPDATE will now affect bar but not foo. This is more useful and
consistent than the original 8.4 behavior, which tried to propagate FOR UPDATE
into the WITH query but always failed due to assorted implementation
restrictions. Even though we are in process of removing those restrictions,
it seems correct on philosophical grounds to not let the outer query's
FOR UPDATE affect the WITH query.
In passing, fix isLockedRel which frequently got things wrong in
nested-subquery cases: "FOR UPDATE OF foo" applies to an alias foo in the
current query level, not subqueries. This has been broken for a long time,
but it doesn't seem worth back-patching further than 8.4 because the actual
consequences are minimal. At worst the parser would sometimes get
RowShareLock on a relation when it should be AccessShareLock or vice versa.
That would only make a difference if someone were using ExclusiveLock
concurrently, which no standard operation does, and anyway FOR UPDATE
doesn't result in visible changes so it's not clear that the someone would
notice any problem. Between that and the fact that FOR UPDATE barely works
with subqueries at all in existing releases, I'm not excited about worrying
about it.
style by default. Per discussion, there seems to be hardly anything that
really relies on being able to change the regex flavor, so the ability to
select it via embedded options ought to be enough for any stragglers.
Also, if we didn't remove the GUC, we'd really be morally obligated to
mark the regex functions non-immutable, which'd possibly create performance
issues.
Per recent discussion, add_missing_from has been deprecated for long enough to
consider removing, and it's getting in the way of planned parser refactoring.
The system now always behaves as though add_missing_from were OFF.
are named in the UPDATE's SET list.
Note: the schema of pg_trigger has not actually changed; we've just started
to use a column that was there all along. catversion bumped anyway so that
this commit is included in the history of potentially interesting changes
to system catalog contents.
Itagaki Takahiro
ASCII-art style of table output to be upgraded to use Unicode box drawing
characters if desired. By default, psql will use the Unicode characters
whenever client_encoding is UTF8.
The patch forces linestyle=ascii in pg_regress usage, ensuring we don't
break the regression tests in Unicode locales.
Roger Leigh
* Stop escaping ? and {. As of SQL:2008, SIMILAR TO is defined to have
POSIX-compatible interpretation of ? as well as {m,n} and related constructs,
so we should allow these things through to our regex engine.
* Escape ^ and $. It appears that our regex engine will treat ^^ at the
beginning of the string the same as ^, and similarly for $$ at the end of
the string, which meant that SIMILAR TO was effectively ignoring ^ at the
start of the pattern and $ at the end. Since these are not supposed to be
metacharacters, this is a bug.
The second part of this is arguably a back-patchable bug fix, but I'm
hesitant to do that because it might break applications that are expecting
something like "col SIMILAR TO '^foo$'" to work like a POSIX pattern.
Seems safer to only change it at a major version boundary.
Per discussion of an example from Doug Gorley.
They are now handled by a new plan node type called ModifyTable, which is
placed at the top of the plan tree. In itself this change doesn't do much,
except perhaps make the handling of RETURNING lists and inherited UPDATEs a
tad less klugy. But it is necessary preparation for the intended extension of
allowing RETURNING queries inside WITH.
Marko Tiikkaja
Add a variant of pg_get_triggerdef with a second argument "pretty" that
causes the output to be formatted in the way pg_dump used to do. Use this
variant in pg_dump with server versions >= 8.5.
This insulates pg_dump from most future trigger feature additions, such as
the upcoming column triggers patch.
Author: Itagaki Takahiro <itagaki.takahiro@oss.ntt.co.jp>