aboutsummaryrefslogtreecommitdiff
path: root/src/backend/utils/misc/pg_controldata.c
Commit message (Collapse)AuthorAge
* Add default_char_signedness field to ControlFileData.Masahiko Sawada2025-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The signedness of the 'char' type in C is implementation-dependent. For instance, 'signed char' is used by default on x86 CPUs, while 'unsigned char' is used on aarch CPUs. Previously, we accidentally let C implementation signedness affect persistent data. This led to inconsistent results when comparing char data across different platforms. This commit introduces a new 'default_char_signedness' field in ControlFileData to store the signedness of the 'char' type. While this change does not encourage the use of 'char' without explicitly specifying its signedness, this field can be used as a hint to ensure consistent behavior for pre-v18 data files that store data sorted by the 'char' type on disk (e.g., GIN and GiST indexes), especially in cross-platform replication scenarios. Newly created database clusters unconditionally set the default char signedness to true. pg_upgrade (with an upcoming commit) changes this flag for clusters if the source database cluster has signedness=false. As a result, signedness=false setting will become rare over time. If we had known about the problem during the last development cycle that forced initdb (v8.3), we would have made all clusters signed or all clusters unsigned. Making pg_upgrade the only source of signedness=false will cause the population of database clusters to converge toward that retrospective ideal. Bump catalog version (for the catalog changes) and PG_CONTROL_VERSION (for the additions in ControlFileData). Reviewed-by: Noah Misch <noah@leadboat.com> Discussion: https://postgr.es/m/CB11ADBC-0C3F-4FE0-A678-666EE80CBB07%40amazon.com
* Update copyright for 2025Bruce Momjian2025-01-01
| | | | Backpatch-through: 13
* Remove unused #include's from backend .c filesPeter Eisentraut2024-03-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | as determined by include-what-you-use (IWYU) While IWYU also suggests to *add* a bunch of #include's (which is its main purpose), this patch does not do that. In some cases, a more specific #include replaces another less specific one. Some manual adjustments of the automatic result: - IWYU currently doesn't know about includes that provide global variable declarations (like -Wmissing-variable-declarations), so those includes are being kept manually. - All includes for port(ability) headers are being kept for now, to play it safe. - No changes of catalog/pg_foo.h to catalog/pg_foo_d.h, to keep the patch from exploding in size. Note that this patch touches just *.c files, so nothing declared in header files changes in hidden ways. As a small example, in src/backend/access/transam/rmgr.c, some IWYU pragma annotations are added to handle a special case there. Discussion: https://www.postgresql.org/message-id/flat/af837490-6b2f-46df-ba05-37ea6a6653fc%40eisentraut.org
* Update copyright for 2024Bruce Momjian2024-01-03
| | | | | | | | Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
* Acquire ControlFileLock in relevant SQL functions.Thomas Munro2023-10-16
| | | | | | | | | | | | | | Commit dc7d70ea added functions that read the control file, but didn't acquire ControlFileLock. With unlucky timing, file systems that have weak interlocking like ext4 and ntfs could expose partially overwritten contents, and the checksum would fail. Back-patch to all supported releases. Reviewed-by: David Steele <david@pgmasters.net> Reviewed-by: Anton A. Melnikov <aamelnikov@inbox.ru> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/20221123014224.xisi44byq3cf5psi%40awork3.anarazel.de
* Update copyright for 2023Bruce Momjian2023-01-02
| | | | Backpatch-through: 11
* Switch some system functions to use get_call_result_type()Michael Paquier2022-12-21
| | | | | | | | | | | | | | | | | This shaves some code by replacing the combinations of CreateTemplateTupleDesc()/TupleDescInitEntry() hardcoding a mapping of the attributes listed in pg_proc.dat by get_call_result_type() to build the TupleDesc needed for the rows generated. get_call_result_type() is more expensive than the former style, but this removes some duplication with the lists of OUT parameters (pg_proc.dat and the attributes hardcoded in these code paths). This is applied to functions that are not considered as critical (aka that could be called repeatedly for monitoring purposes). Author: Bharath Rupireddy Reviewed-by: Robert Haas, Álvaro Herrera, Tom Lane, Michael Paquier Discussion: https://postgr.es/m/CALj2ACV23HW5HP5hFjd89FNS-z5X8r2jNXdMXcpN2BgTtKd87w@mail.gmail.com
* Revert 56-bit relfilenode change and follow-up commits.Robert Haas2022-09-28
| | | | | | | | There are still some alignment-related failures in the buildfarm, which might or might not be able to be fixed quickly, but I've also just realized that it increased the size of many WAL records by 4 bytes because a block reference contains a RelFileLocator. The effect of that hasn't been studied or discussed, so revert for now.
* Increase width of RelFileNumbers from 32 bits to 56 bits.Robert Haas2022-09-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | RelFileNumbers are now assigned using a separate counter, instead of being assigned from the OID counter. This counter never wraps around: if all 2^56 possible RelFileNumbers are used, an internal error occurs. As the cluster is limited to 2^64 total bytes of WAL, this limitation should not cause a problem in practice. If the counter were 64 bits wide rather than 56 bits wide, we would need to increase the width of the BufferTag, which might adversely impact buffer lookup performance. Also, this lets us use bigint for pg_class.relfilenode and other places where these values are exposed at the SQL level without worrying about overflow. This should remove the need to keep "tombstone" files around until the next checkpoint when relations are removed. We do that to keep RelFileNumbers from being recycled, but now that won't happen anyway. However, this patch doesn't actually change anything in this area; it just makes it possible for a future patch to do so. Dilip Kumar, based on an idea from Andres Freund, who also reviewed some earlier versions of the patch. Further review and some wordsmithing by me. Also reviewed at various points by Ashutosh Sharma, Vignesh C, Amul Sul, Álvaro Herrera, and Tom Lane. Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com
* Update copyright for 2022Bruce Momjian2022-01-07
| | | | Backpatch-through: 10
* Fix incorrect field count in pg_control_checkpoint()Michael Paquier2021-12-26
| | | | | | | | | 18 columns are generated in this function, but we had enough space for 19 of them. Introduced by 4b0d28d. Author: Bharath Rupireddy Reviewed-by: Justin Pryzby, Euler Taveira Discussion: https://postgr.es/m/CALj2ACVQ=hAs=sT0n4xriimqRrrgECySfg_tSqA+26Rb_yfs2A@mail.gmail.com
* Update copyright for 2021Bruce Momjian2021-01-02
| | | | Backpatch-through: 9.5
* Revert "Add key management system" (978f869b99) & later commitsBruce Momjian2020-12-27
| | | | | | | | | | The patch needs test cases, reorganization, and cfbot testing. Technically reverts commits 5c31afc49d..e35b2bad1a (exclusive/inclusive) and 08db7c63f3..ccbe34139b. Reported-by: Tom Lane, Michael Paquier Discussion: https://postgr.es/m/E1ktAAG-0002V2-VB@gemulon.postgresql.org
* Add key management systemBruce Momjian2020-12-25
| | | | | | | | | | | | | | | This adds a key management system that stores (currently) two data encryption keys of length 128, 192, or 256 bits. The data keys are AES256 encrypted using a key encryption key, and validated via GCM cipher mode. A command to obtain the key encryption key must be specified at initdb time, and will be run at every database server start. New parameters allow a file descriptor open to the terminal to be passed. pg_upgrade support has also been added. Discussion: https://postgr.es/m/CA+fd4k7q5o6Nc_AaX6BcYM9yqTbC6_pnH-6nSD=54Zp6NBQTCQ@mail.gmail.com Discussion: https://postgr.es/m/20201202213814.GG20285@momjian.us Author: Masahiko Sawada, me, Stephen Frost
* Don't use custom OID symbols in pg_type.dat, either.Tom Lane2020-10-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | On the same reasoning as in commit 36b931214, forbid using custom oid_symbol macros in pg_type as well as pg_proc, so that we always rely on the predictable macro names generated by genbki.pl. We do continue to grant grandfather status to the names CASHOID and LSNOID, although those are now considered deprecated aliases for the preferred names MONEYOID and PG_LSNOID. This is because there's likely to be client-side code using the old names, and this bout of neatnik-ism doesn't quite seem worth breaking client code. There might be a case for grandfathering EVTTRIGGEROID, too, since externally-maintained PLs may reference that symbol. But renaming such references to EVENT_TRIGGEROID doesn't seem like a particularly heavy lift --- we make far more significant backend API changes in every major release. For now I didn't add that, but we could reconsider if there's pushback. The other names changed here seem pretty unlikely to have any outside uses. Again, we could add alias macros if there are complaints, but for now I didn't. As before, no need for a catversion bump. John Naylor Discussion: https://postgr.es/m/CAFBsxsHpCbjfoddNGpnnnY5pHwckWfiYkMYSF74PmP1su0+ZOw@mail.gmail.com
* Rename VariableCacheData.nextFullXid to nextXid.Andres Freund2020-08-11
| | | | | | | | | Including Full in variable names duplicates the type information and leads to overly long names. As FullTransactionId cannot accidentally be casted to TransactionId that does not seem necessary. Author: Andres Freund Discussion: https://postgr.es/m/20200724011143.jccsyvsvymuiqfxu@alap3.anarazel.de
* Clean up newlines following left parenthesesAlvaro Herrera2020-01-30
| | | | | | | | | | | | We used to strategically place newlines after some function call left parentheses to make pgindent move the argument list a few chars to the left, so that the whole line would fit under 80 chars. However, pgindent no longer does that, so the newlines just made the code vertically longer for no reason. Remove those newlines, and reflow some of those lines for some extra naturality. Reviewed-by: Michael Paquier, Tom Lane Discussion: https://postgr.es/m/20200129200401.GA6303@alvherre.pgsql
* Update copyrights for 2020Bruce Momjian2020-01-01
| | | | Backpatch-through: update all files in master, backpatch legal files through 9.4
* Fix tuple column count in pg_control_init().Tom Lane2019-12-10
| | | | | | | | Oversight in commit 2e4db241b. Nathan Bossart Discussion: https://postgr.es/m/1B616360-396A-4482-AA28-375566C86160@amazon.com
* Remove configure --disable-float4-byvalPeter Eisentraut2019-11-21
| | | | | | | | | | | This build option was only useful to maintain compatibility for version-0 functions, but those are no longer supported, so this option can be removed. float4 is now always pass-by-value; the pass-by-reference code path is completely removed. Discussion: https://www.postgresql.org/message-id/flat/f3e1e576-2749-bbd7-2d57-3f9dcf75255a@2ndquadrant.com
* Make the order of the header file includes consistent in backend modules.Amit Kapila2019-11-12
| | | | | | | | | | | Similar to commits 7e735035f2 and dddf4cdc33, this commit makes the order of header file inclusion consistent for backend modules. In the passing, removed a couple of duplicate inclusions. Author: Vignesh C Reviewed-by: Kuntal Ghosh and Amit Kapila Discussion: https://postgr.es/m/CALDaNm2Sznv8RR6Ex-iJO6xAdsxgWhCoETkaYX=+9DW3q0QCfA@mail.gmail.com
* Unified logging system for command-line programsPeter Eisentraut2019-04-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This unifies the various ad hoc logging (message printing, error printing) systems used throughout the command-line programs. Features: - Program name is automatically prefixed. - Message string does not end with newline. This removes a common source of inconsistencies and omissions. - Additionally, a final newline is automatically stripped, simplifying use of PQerrorMessage() etc., another common source of mistakes. - I converted error message strings to use %m where possible. - As a result of the above several points, more translatable message strings can be shared between different components and between frontends and backend, without gratuitous punctuation or whitespace differences. - There is support for setting a "log level". This is not meant to be user-facing, but can be used internally to implement debug or verbose modes. - Lazy argument evaluation, so no significant overhead if logging at some level is disabled. - Some color in the messages, similar to gcc and clang. Set PG_COLOR=auto to try it out. Some colors are predefined, but can be customized by setting PG_COLORS. - Common files (common/, fe_utils/, etc.) can handle logging much more simply by just using one API without worrying too much about the context of the calling program, requiring callbacks, or having to pass "progname" around everywhere. - Some programs called setvbuf() to make sure that stderr is unbuffered, even on Windows. But not all programs did that. This is now done centrally. Soft goals: - Reduces vertical space use and visual complexity of error reporting in the source code. - Encourages more deliberate classification of messages. For example, in some cases it wasn't clear without analyzing the surrounding code whether a message was meant as an error or just an info. - Concepts and terms are vaguely aligned with popular logging frameworks such as log4j and Python logging. This is all just about printing stuff out. Nothing affects program flow (e.g., fatal exits). The uses are just too varied to do that. Some existing code had wrappers that do some kind of print-and-exit, and I adapted those. I tried to keep the output mostly the same, but there is a lot of historical baggage to unwind and special cases to consider, and I might not always have succeeded. One significant change is that pg_rewind used to write all error messages to stdout. That is now changed to stderr. Reviewed-by: Donald Dong <xdong@csumb.edu> Reviewed-by: Arthur Zakirov <a.zakirov@postgrespro.ru> Discussion: https://www.postgresql.org/message-id/flat/6a609b43-4f57-7348-6480-bd022f924310@2ndquadrant.com
* Add basic infrastructure for 64 bit transaction IDs.Thomas Munro2019-03-28
| | | | | | | | | | | | | | | | | | | | | | | | Instead of inferring epoch progress from xids and checkpoints, introduce a 64 bit FullTransactionId type and use it to track xid generation. This fixes an unlikely bug where the epoch is reported incorrectly if the range of active xids wraps around more than once between checkpoints. The only user-visible effect of this commit is to correct the epoch used by txid_current() and txid_status(), also visible with pg_controldata, in those rare circumstances. It also creates some basic infrastructure so that later patches can use 64 bit transaction IDs in more places. The new type is a struct that we pass by value, as a form of strong typedef. This prevents the sort of accidental confusion between TransactionId and FullTransactionId that would be possible if we were to use a plain old uint64. Author: Thomas Munro Reported-by: Amit Kapila Reviewed-by: Andres Freund, Tom Lane, Heikki Linnakangas Discussion: https://postgr.es/m/CAA4eK1%2BMv%2Bmb0HFfWM9Srtc6MVe160WFurXV68iAFMcagRZ0dQ%40mail.gmail.com
* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Remove WITH OIDS support, change oid catalog column visibility.Andres Freund2018-11-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
* Reorganize partitioning codeAlvaro Herrera2018-04-14
| | | | | | | | | | | | | | | | | | | | | | There's been a massive addition of partitioning code in PostgreSQL 11, with little oversight on its placement, resulting in a catalog/partition.c with poorly defined boundaries and responsibilities. This commit tries to set a couple of distinct modules to separate things a little bit. There are no code changes here, only code movement. There are three new files: src/backend/utils/cache/partcache.c src/include/partitioning/partdefs.h src/include/utils/partcache.h The previous arrangement of #including catalog/partition.h almost everywhere is no more. Authors: Amit Langote and Álvaro Herrera Discussion: https://postgr.es/m/98e8d509-790a-128c-be7f-e48a5b2d8d97@lab.ntt.co.jp https://postgr.es/m/11aa0c50-316b-18bb-722d-c23814f39059@lab.ntt.co.jp https://postgr.es/m/143ed9a4-6038-76d4-9a55-502035815e68@lab.ntt.co.jp https://postgr.es/m/20180413193503.nynq7bnmgh6vs5vm@alvherre.pgsql
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Fix pg_control_checkpoint from commit 4b0d28de06Simon Riggs2017-11-21
| | | | | Author: Simon Riggs <simon@2ndQuadrant.com> Reported-By: Andreas Seltenreich <seltenreich@gmx.de>
* Remove secondary checkpointSimon Riggs2017-11-07
| | | | | | | | | | Previously server reserved WAL for last two checkpoints, which used too much disk space for small servers. Bumps PG_CONTROL_VERSION Author: Simon Riggs <simon@2ndQuadrant.com> Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
* Make WAL segment size configurable at initdb time.Andres Freund2017-09-19
| | | | | | | | | | | | | | | | | | | | | | | For performance reasons a larger segment size than the default 16MB can be useful. A larger segment size has two main benefits: Firstly, in setups using archiving, it makes it easier to write scripts that can keep up with higher amounts of WAL, secondly, the WAL has to be written and synced to disk less frequently. But at the same time large segment size are disadvantageous for smaller databases. So far the segment size had to be configured at compile time, often making it unrealistic to choose one fitting to a particularly load. Therefore change it to a initdb time setting. This includes a breaking changes to the xlogreader.h API, which now requires the current segment size to be configured. For that and similar reasons a number of binaries had to be taught how to recognize the current segment size. Author: Beena Emerson, editorialized by Andres Freund Reviewed-By: Andres Freund, David Steele, Kuntal Ghosh, Michael Paquier, Peter Eisentraut, Robert Hass, Tushar Ahuja Discussion: https://postgr.es/m/CAOG9ApEAcQ--1ieKbhFzXSQPw_YLmepaa4hNdnY5+ZULpt81Mw@mail.gmail.com
* Phase 3 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | Don't move parenthesized lines to the left, even if that means they flow past the right margin. By default, BSD indent lines up statement continuation lines that are within parentheses so that they start just to the right of the preceding left parenthesis. However, traditionally, if that resulted in the continuation line extending to the right of the desired right margin, then indent would push it left just far enough to not overrun the margin, if it could do so without making the continuation line start to the left of the current statement indent. That makes for a weird mix of indentations unless one has been completely rigid about never violating the 80-column limit. This behavior has been pretty universally panned by Postgres developers. Hence, disable it with indent's new -lpl switch, so that parenthesized lines are always lined up with the preceding left paren. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Rename WAL-related functions and views to use "lsn" not "location".Tom Lane2017-05-11
| | | | | | | | | | | | | | | Per discussion, "location" is a rather vague term that could refer to multiple concepts. "LSN" is an unambiguous term for WAL locations and should be preferred. Some function names, view column names, and function output argument names used "lsn" already, but others used "location", as well as yet other terms such as "wal_position". Since we've already renamed a lot of things in this area from "xlog" to "wal" for v10, we may as well incur a bit more compatibility pain and make these names all consistent. David Rowley, minor additional docs hacking by me Discussion: https://postgr.es/m/CAKJS1f8O0njDKe8ePFQ-LK5-EjwThsDws6ohJ-+c6nWK+oUxtg@mail.gmail.com
* Remove pg_control's enableIntTimes field.Tom Lane2017-02-23
| | | | | | | | | | | | | | | We don't need it any more. pg_controldata continues to report that date/time type storage is "64-bit integers", but that's now a hard-wired behavior not something it sees in the data. This avoids breaking pg_upgrade, and perhaps other utilities that inspect pg_control this way. Ditto for pg_resetwal. I chose to remove the "bigint_timestamps" output column of pg_control_init(), though, as that function hasn't been around long and probably doesn't have ossified users. Discussion: https://postgr.es/m/26788.1487455319@sss.pgh.pa.us
* Update copyright via script for 2017Bruce Momjian2017-01-03
|
* Fix CRC check handling in get_controlfilePeter Eisentraut2016-09-28
| | | | | | | | The previous patch broke this by returning NULL for a failed CRC check, which pg_controldata would then try to read. Fix by returning the result of the CRC check in a separate argument. Michael Paquier and myself
* pg_ctl: Detect current standby state from pg_controlPeter Eisentraut2016-09-21
| | | | | | | | | | pg_ctl used to determine whether a server was in standby mode by looking for a recovery.conf file. With this change, it instead looks into pg_control, which is potentially more accurate. There are also occasional discussions about removing recovery.conf, so this removes one dependency. Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
* pgindent run for 9.6Robert Haas2016-06-09
|
* Expose control file data via SQL accessible functions.Joe Conway2016-03-05
Add four new SQL accessible functions: pg_control_system(), pg_control_checkpoint(), pg_control_recovery(), and pg_control_init() which expose a subset of the control file data. Along the way move the code to read and validate the control file to src/common, where it can be shared by the new backend functions and the original pg_controldata frontend program. Patch by me, significant input, testing, and review by Michael Paquier.
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-07 14:41:20 +0000