MySQLの以前のバージョンには、あまり知られていない 「隠し 」ファンクションがあったことをご存知でしょうか？
2012年10月16日にリリースされた5.6.8rcでは、そのうちの1つが消えてしまいました。
それがどれなのかご存知でしょうか？
SHOW AUTHORS
SHOW AUTHORS は5.6.7rcまで存在し、MySQLの初期開発者のリストを表示していました。
古いバージョンをインストールして試してみましょう：
mysql [localhost:5561] {msandbox} ((none)) > select @@version;
+-----------+
| @@version |
+-----------+
| 5.5.61 |
+-----------+
1 row in set (0.00 sec)
mysql [localhost:5561] {msandbox} ((none)) > show authors;
+--------------------------------+---------------------------------------+----------------------------------------------------------------------+
| Name | Location | Comment |
+--------------------------------+---------------------------------------+----------------------------------------------------------------------+
| Brian (Krow) Aker | Seattle, WA, USA | Architecture, archive, federated, bunch of little stuff :) |
| Marc Alff | Denver, CO, USA | Signal, Resignal, Performance schema |
| Venu Anuganti | | Client/server protocol (4.1) |
| David Axmark | Uppsala, Sweden | Small stuff long time ago, Monty ripped it out! |
| Alexander (Bar) Barkov | Izhevsk, Russia | Unicode and character sets (4.1) |
| Omer BarNir | Sunnyvale, CA, USA | Testing (sometimes) and general QA stuff |
| Guilhem Bichot | Bordeaux, France | Replication (since 4.0) |
| John Birrell | | Emulation of pthread_mutex() for OS/2 |
| Andreas F. Bobak | | AGGREGATE extension to user-defined functions |
| Alexey Botchkov (Holyfoot) | Izhevsk, Russia | GIS extensions (4.1), embedded server (4.1), precision math (5.0) |
| Reggie Burnett | Nashville, TN, USA | Windows development, Connectors |
| Oleksandr Byelkin | Lugansk, Ukraine | Query Cache (4.0), Subqueries (4.1), Views (5.0) |
| Kent Boortz | Orebro, Sweden | Test platform, and general build stuff |
| Tim Bunce | | mysqlhotcopy |
| Yves Carlier | | mysqlaccess |
| Joshua Chamas | Cupertino, CA, USA | Concurrent insert, extended date syntax |
| Petr Chardin | Moscow, Russia | Instance Manager (5.0), Server log tables (5.1) |
| Wei-Jou Chen | | Chinese (Big5) character set |
| Albert Chin-A-Young | | Tru64 port, large file support, better TCP wrappers support |
| Jorge del Conde | Mexico City, Mexico | Windows development |
| Antony T. Curtis | Norwalk, CA, USA | Parser, port to OS/2, storage engines and some random stuff |
| Yuri Dario | | OS/2 port |
| Andrei Elkin | Espoo, Finland | Replication |
| Patrick Galbraith | Sharon, NH | Federated Engine, mysqlslap |
| Sergei Golubchik | Kerpen, Germany | Full-text search, precision math |
| Lenz Grimmer | Hamburg, Germany | Production (build and release) engineering |
| Nikolay Grishakin | Austin, TX, USA | Testing - Server |
| Wei He | | Chinese (GBK) character set |
| Eric Herman | Amsterdam, Netherlands | Bug fixing - federated |
| Andrey Hristov | Walldorf, Germany | Event scheduler (5.1) |
| Alexander (Alexi) Ivanov | St. Petersburg, Russia | Replication |
| Mattias Jonsson | Uppsala, Sweden | Partitioning |
| Alexander (Salle) Keremidarski | Sofia, Bulgaria | Bug fixing |
| Mats Kindahl | Storvreta, Sweden | Replication |
| Serge Kozlov | Velikie Luki, Russia | Testing - Cluster |
| Hakan Küçükyılmaz | Walldorf, Germany | Testing - Server |
| Greg (Groggy) Lehey | Uchunga, SA, Australia | Backup |
| Matthias Leich | Berlin, Germany | Testing - Server |
| Dmitri Lenev | Moscow, Russia | Time zones support (4.1), Triggers (5.0) |
| Arjen Lentz | Brisbane, Australia | Documentation (2001-2004), Dutch error messages, LOG2() |
| Marc Liyanage | | Created Mac OS X packages |
| Kelly Long | Denver, CO, USA | Pool Of Threads |
| Zarko Mocnik | | Sorting for Slovenian language |
| Per-Erik Martin | Uppsala, Sweden | Stored Procedures (5.0) |
| Alexis Mikhailov | | User-defined functions |
| Sinisa Milivojevic | Larnaca, Cyprus | UNION (4.0), Subqueries in FROM clause (4.1), many other features |
| Jonathan (Jeb) Miller | Kyle, TX, USA | Testing - Cluster, Replication |
| Elliot Murphy | Cocoa, FL, USA | Replication and backup |
| Kristian Nielsen | Copenhagen, Denmark | General build stuff |
| Pekka Nouisiainen | Stockholm, Sweden | NDB Cluster: BLOB support, character set support, ordered indexes |
| Alexander Nozdrin | Moscow, Russia | Bug fixing (Stored Procedures, 5.0) |
| Per Eric Olsson | | Testing of dynamic record format |
| Jonas Oreland | Stockholm, Sweden | NDB Cluster, Online Backup, lots of other things |
| Konstantin Osipov | Moscow, Russia | Prepared statements (4.1), Cursors (5.0) |
| Alexander (Sasha) Pachev | Provo, UT, USA | Statement-based replication, SHOW CREATE TABLE, mysql-bench |
| Irena Pancirov | | Port to Windows with Borland compiler |
| Jan Pazdziora | | Czech sorting order |
| Benjamin Pflugmann | | Extended MERGE storage engine to handle INSERT |
| Igor Romanenko | | mysqldump |
| Mikael Ronström | Stockholm, Sweden | NDB Cluster, Partitioning (5.1), Optimizations |
| Tõnu Samuel | | VIO interface, other miscellaneous features |
| Carsten Segieth (Pino) | Fredersdorf, Germany | Testing - Server |
| Martin Sköld | Stockholm, Sweden | NDB Cluster: Unique indexes, integration into MySQL |
| Timothy Smith | Auckland, New Zealand | Dynamic character sets, parts of the build system, libmysqld |
| Miguel Solorzano | Florianopolis, Santa Catarina, Brazil | Windows development, Windows NT service |
| Punita Srivastava | Austin, TX, USA | Testing - Merlin |
| Alexey Stroganov (Ranger) | Lugansk, Ukraine | Testing - Benchmarks |
| Ingo Strüwing | Berlin, Germany | Bug fixing |
| Magnus Svensson | Öregrund, Sweden | NDB Cluster: Integration into MySQL, test framework |
| Zeev Suraski | | FROM_UNIXTIME(), ENCRYPT() |
| TAMITO | | The _MB character set macros and UJIS and SJIS character sets |
| Jani Tolonen | Helsinki, Finland | mysqlimport, extensions to command-line clients, PROCEDURE ANALYSE() |
| Lars Thalmann | Stockholm, Sweden | Replication and cluster development |
| Tomas Ulin | Stockholm, Sweden | NDB Cluster: Configuration, installation |
| Gianmassimo Vigazzola | | Initial Windows port |
| Sergey Vojtovich | Izhevsk, Russia | Plugins infrastructure (5.1) |
| Matt Wagner | Northfield, MN, USA | Bug fixing |
| Jim Winstead Jr. | Los Angeles, CA, USA | Bug fixing |
| Michael (Monty) Widenius | Tusby, Finland | Lead developer and main author |
| Peter Zaitsev | Tacoma, WA, USA | SHA1(), AES_ENCRYPT(), AES_DECRYPT(), bug fixing |
+--------------------------------+---------------------------------------+----------------------------------------------------------------------+
80 rows in set, 1 warning (0.00 sec)
この出力内容は、sql/authors.h ファイルから取得しています。
このコマンドは MySQL バージョン 5.1.3 で導入されました：
5.5.61から5.6.7rcの間に追加された名前は1つ (Evgeny Potemkin) のみで、該当テーブルの更新を終了し削除されました。
同じ状況は別のあまり知られていないコマンドでも発生しています:
SHOW CONTRIBUTORS
後述のようにこのコマンドも削除されました:
mysql [localhost:5561] {msandbox} ((none)) > show contributors;
+-------------------+---------------------+-------------------------------------+
| Name | Location | Comment |
+-------------------+---------------------+-------------------------------------+
| Ronald Bradford | Brisbane, Australia | EFF contribution for UC2006 Auction |
| Sheeri Kritzer | Boston, Mass. USA | EFF contribution for UC2006 Auction |
| Mark Shuttleworth | London, UK. | EFF contribution for UC2006 Auction |
+-------------------+---------------------+-------------------------------------+
3 rows in set, 1 warning (0.00 sec)
The content was defined in sql/contributors.h.
この出力内容は、sql/contributors.h ファイルから取得しています。
このコマンドは MySQL バージョン 5.1.12 で導入されました：
他に変わったコマンドに見覚えのある方は、ぜひお知らせください！