You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window. Reload to refresh your session. You switched accounts on another tab or window. Reload to refresh your session. Dismiss alert
InnoDBã¯MyISAMã¨æ¯è¼ãã¦å®å ¨(OSã¯ã©ãã·ã¥ãé»æºæãçºçãã¦ããã¼ãã«ãå£ããªã)åãæ¸ãè¾¼ã¿ãé ãããã¼ã¿ãã¼ã¹å±ããããããã¨ãããã¯å½ç¶ã®ãã¨ã§MyISAMããããããã ãã¨ãããã¨ã«ãªããã ããããããªããã¯ã¢ããæ©è½ã®ã¤ããRAIDã«ã¼ãã使ããã ãã¨ãã話ã«ãªããã§ããMyISAMã使ã£ã¦ããã¦ã§ãå±ããã®ç¾å ´ã§ã¯ãå ´åã«ãã£ã¦å¤å°ãã¼ã¿ãæ¶ãã¦ããã¾ããªããããå®ããã¼ãã¦ã§ã¢ã§å¤§éã®ã¢ã¯ã»ã¹ãæããã... ã£ã¦ä¹é¢ãããããããªãããªã¼ã¨æã£ã¦ãã ãã®ãããªå ´åã«ã¯ãmy.cnf ã® innodb_flush_log_at_trx_commit ãã©ã¡ã¼ã¿ã調æ´ãããã¨ã§ãMyISAMã«æ¯è©ããæ¸ãè¾¼ã¿é度ãå¾ããã¨ãã§ãã(ãã®ããããã¯ã©ãã·ã¥ãé»æºæã®å ´åã¯ãè¨å®ã«ãã£ã¦ç´è¿ï¼ç§ä»¥å ã®å¤æ´ã失ããã)ã ä»ã®ãã©ã¡ã¼ã¿ãå«ãã¦æ¸ãã¦ããã¨ããã¼ã¿ãã¼
æ¾ä¿¡æ°ã®ã MyISAMã¨InnoDBã®ã©ã¡ãã使ãã¹ãã Twitterã§è©±é¡ã«ãªã£ã¦ãã®ã§ç°¡åã«ã¾ã¨ãã¾ããã ã¨ããã¨ã³ããªã人æ°ãåãã¦ããããæ¾ä¿¡æ°ãè¨ãããã«æè¿ã¯Twitterã§MySQLé¢é£ã®è©±é¡ãçµæ§å¢ãã¦ãã¦ããããã«æããTwitterã®æµè¡ã®å¢ãã¯åã¾ãããä»ã¯å³ãåãã¦ãå·¦ãåãã¦ãTwitterãå¯ã¦ãè¦ãã¦ãTwitterãç«ãæåãTwitterã¨ããé°å²æ°ã§ãããå¾ã£ã¦MySQLãTwitterã§çãä¸ããã®ã¯å½ç¶ã®æãè¡ãã¨ãããã§ããããTwitterãæ´»ç¨ããªãæã¯ãªãã ãããMySQLé¢é£ã®è©±ã§çãä¸ããã¨è¨ã£ã¦ããããã誰ããã©ãã¼ããã°è©±ã«å ¥ãããã ãï¼ï¼ãã¨å¤ãã®çããã¯çåã«æããããã¨ã ãããããã§ãä»æ¥ã¯MySQLé¢é£ã®Twitterã¢ã«ã¦ã³ããç¬æã¨åè¦ã¨æã¨åæ°ã¨åªåããã£ã¦ç´¹ä»ãããMySQLã®æ å ±ã欲ãã人ããããã¯è©±é¡ã®è¼ªã«
MySQL 5.1ã®mysqldumpslowã使ãã¨ãã¥ã¼ãã³ã°ã楽ã«ãªãï¼ã¨ãã話é¡ã§ãã mysqldumpslowã¯ãã¨ãã¨MySQLã«ä»å±ãã¦ãããã¼ã«ã§ãã¹ãã¼ã¯ã¨ãªãã°ãéè¨ãã¦ããããã®ã§ããããèªä½ã¯MySQL 5.1ã§ç¹ã«å¤ãã£ãã¨ããã¯ããã¾ããããã¹ãã¼ã¯ã¨ãªãã°æ¬ä½ã®æ¹ãæ©è½å¼·åããã¦ãããããçµã¿åãããã¨ãªããªã便å©ã«ãªã£ã¦ãã¾ããMySQL 5.1ã«ãããã¹ãã¼ã¯ã¨ãªãã°ã®ä¸»ãªæ©è½å¼·åã¯ä»¥ä¸ã®ä¸ç¹ã§ãã long_query_timeã«1ç§æªæºã®å¤ãè¨å®ã§ããããã«ãªã£ãã åºåå ãè¨å®ã§ããããã«ãªã£ãã ãããã®è¨å®ããªã³ã©ã¤ã³ã§å¤æ´ã§ããããã«ãªã£ãã ããã§ã©ããªããã¨ããã¨ãMySQLã®æ§è½åæããããã¨æã£ãã¨ãã«ããµã¼ããæ¢ããã«ãã®å ´ã§ mysql> set global slow_query_log = 1; mysql> set glob
MySQLã®InnoDBã¹ãã¬ã¼ã¸ã¨ã³ã¸ã³ã¯è¡ããã¯ããµãã¼ããã¦ãã¾ãããããOracleã¨åãæè¦ã§ã¢ããªã±ã¼ã·ã§ã³ãä½ã£ã¦ããã¨ãæãã¬ã¨ããã§ãããããã¯ã«åºããããã¨ãããã¾ããããã¯InnoDBã®ããã¯ç¯å²ãOracleãããå¾®å¦ã«åºãããã§ãã å®éã®ä¾ã§ç¢ºèªãã¦ã¿ã¾ãããã mysql> select * from t; +----+------+ | c1 | c2 | +----+------+ | 10 | a | | 15 | a | | 20 | a | | 25 | a | | 30 | a | | 35 | a | | 40 | a | | 45 | a | | 50 | a | +----+------+c1åã¯ä¸»ãã¼ã«ãªã£ã¦ãã¾ãã1ã¤ãã®ã»ãã·ã§ã³ã§ä»¥ä¸ã®SQLãå®è¡ãã¾ãã mysql> set tx_isolation = 'repeatable-r
ã¬ã³ã¿ã«ãµã¼ããªãããããã®ã¬ã³ã¿ã«ãµã¼ããï¼ æé¡æç®ã§ããã131åã缶ã¸ã¥ã¼ã¹1æ¬åã®ãå¤æ®µã§ä½¿ããæ ¼å®ãã©ã³ããããã¸ãã¹ã«ã使ããå¤æ©è½ï¼å¤§å®¹éãã©ã³ã¾ã§ã ç¨éã¨äºç®ã«åããã¦ãã©ã³ãé¸ã¹ã¾ãã ããã«ãã«ããã¡ã¤ã³å¯¾å¿ã§ã¡ã¼ã«ã¢ãã¬ã¹ãç¡å¶éãç¡æã¦ã¤ã«ã¹ã¹ãã£ã³ãç¡æé»è©±ãµãã¼ããããã®ã§å®å¿ã㦠ãå©ç¨ããã ããå ±ç¨ã¬ã³ã¿ã«ãµã¼ããµã¼ãã¹ã§ãã
ãããã«è¦éããªã話ãå¤ã ãã£ãã®ã§ãã¡ã¨èª¿ã¹ã¦ã¿ãã ã§â¦å¤§åè¦ãã¦ããããã¤ã³ãã¯å¤åãï¼ã¤ã®èªååãã ã¾ãããããããã®ã¯ãæåã³ã¼ãã®èªååãã å½¼ãçã«ã¯ãEUCã¨ãã¦ã®ããã¯ãããã¨UTF-8ã¨ãã¦ã®ããã¯ãããããã¤ã¾ã euc('ãã¯ãã') = utf-8('ãã¯ãã')ããtrueã«ãããããã ã ã¾ãããããã§ããªããé¢åèµ·ããããããã¨ãå¤ã ããã®ã ãã 次ã«ããã¹ãã¼ã¹ããã£ã³ã°ãã®èªååã padding(ããã£ã³ã°)ã¯ããããï¼ ã¼ãããã£ã³ã°ã¨ãããããéã«æ¸ãã¨ããã¼ã¿éã®ä¸è¶³åãä¸å®ã®æåã§åãããã®ã ã§ã charã¨varcharã®éããcharã¯åºå®é·ãªã®ã«å¯¾ãã¦ãvarcharã¯å¯å¤é·ããããå¯å¤é¨åãã©ããã£ã¦ããã£ã¦è¨ãã¨ã大æµã¯ãå é ã®ï¼ãã¤ãã¨ãï¼ãã¤ãã¨ãï¼ãã¤ãã¨ãï¼ãã¤ãã¨ã使ã£ã¦ããã«lengthãåãè¾¼ãã§ããã®ã ç¿»ã£ã¦ãc
MySQL::Sandbox ã¯ãæ軽㫠MySQL ã®ãµã¼ãã¼ãç«ã¡ä¸ãããã¼ã«ã§ãã¡ãã£ã¨ãããã¹ãç°å¢ãæ§ç¯ããã¨ãã«é常ã«ä¾¿å©ãªãããã¯ãã§ãã ã¨ããããã¤ã³ã¹ãã¼ã« $ sudo cpan -i MySQL::Sandboxã§ã¤ã³ã¹ãã¼ã«ãã¦ãã OS ãã¨ã®å®è¡ãã¤ããªããã¦ã³ãã¼ããã¾ããèªåã®æå ã® VM 㯠CentOS 5.2 ãªã®ã§ãmysql-5.0.82-linux-i686-glibc23.tar.gz ããã¦ã³ãã¼ããã¾ããã ã¾ã㯠ã¬ã·ã ã®æåã«ããããã« make_sandbox ãã¦ã¿ã¾ãã $ make_sandbox /path/to/mysql-5.0.82-linux-i686-glibc23.tar.gzãããã㨠/home/zigorou/sandboxes 以ä¸ã«ãµã³ãããã¯ã¹ãåºæ¥ã¦ã¾ããã¤ãã§ã« mysqld ãç«ã¡ä¸ãã£ã¦ãã¾
ãã¼ã¿ãã¼ã¹ã®ééå³ã¯ãããã©ã¼ãã³ã¹ãã¥ã¼ãã³ã°ã«ããã¾ãã ãã¥ã¼ãã³ã°ã«ãã£ã¦ã¯ãåãå¦çã§ã1æéæããå ´åãããã°ã 1ç§ã§çµããã¨ãããã¨ãããå¾ãä¸çã§ãã åã¯DBã®é åã«åãä»ãããè ã®ä¸äººã§ãã DBã¨ããæè¡ã®å¥¥æ·±ããæ°ã«å ¥ã£ã¦ãã¾ãã DBã極ããã¨ãã©ãã®ç¾å ´ã«è¡ã£ã¦ã絶対ã«å¿ è¦ã¨ããã¾ãã ã¾ããã©ãã®ç¾å ´ã«è¡ã£ã¦ãæ£è§£ãå°ãæ¹ç¨å¼ã¯ä¸ç·ãªã®ã§å¿ç¨ãå©ãã®ã§ãã ãããããã®åºæ¬åçãä½ç³»çã«å¦ã¹ãæ段ã¯ãã¾ãããã¾ããã OracleMasterãMCDBAã¨ãã£ãè³æ ¼è©¦é¨ã§ãå¦ã¹ããã¨ã¯éããã¦ã㦠ãã¨ã¯Webã§èª¿ã¹ããªãããã¥ã¢ã«ãèªããªãããããããã¾ããã§ããã ã¨ãã«èã§ããããã©ã¼ãã³ã¹ãã¥ã¼ãã³ã°ã«ã¤ãã¦ã¯ã çµé¨åã§ãã¥ã¼ãã³ã°ãã¦ããé¨åãå¤ãã§ãã OracleãSQLServerãMySQLã¨è²ã ãªDBã®ãã¥ã¼ãã³ã°ããã¦ãã¾ãããã
ORM ãã¦ã§ãã¢ããªã±ã¼ã·ã§ã³é¢é£ã®ã©ã¤ãã©ãªãªã©ã®ãã¹ãã±ã¼ã¹ãæ¸ãã«ããã£ã¦ã¯ã RDBMS ã¸ã®ã¢ã¯ã»ã¹ãå¿ è¦ã«ãªãã¾ããããããSQLite ã®ãããªã¹ã¿ã³ãã¢ãã¼ã³ã®ãã¼ã¿ãã¼ã¹ã¨æ¯è¼ããã¨ããµã¼ãåãã¼ã¿ãã¼ã¹ã§ãã MySQL ã«æ¥ç¶ãã¦ãã¹ããæ¸ãã®ã¯ãæ¢åã® MySQL ã®æ¨©éè¨å®ããã¼ã¿ãã¼ã¹åãæ°ã«ããå¿ è¦ããã£ããã¨ãããããä¸ä¾¿ã§ããããã§ãMySQL ã®ã¤ã³ã¹ã¿ã³ã¹ããã³ãã©ãªãã£ã¬ã¯ããªã«èªåçæãããã¹ããçµãã£ããåé¤ãã¦ããã Perl ã¢ã¸ã¥ã¼ã« Test::mysqld ãæ¸ãã¾ããããããªæãã§ä½¿ãã¾ãã use DBI; use Test::mysqld; use Test::More; my $mysqld = Test::mysqld->new( my_cnf => { 'skip-networking' => '' }, # TCPæ¥ç¶ã
éããªãç æ°ãèªãPHP Internalsã®ã»ãã·ã§ã³ããéããããã£ã¡ã® è¬å¸«ã¯MySQL.comã®äººãè¬æ¼æ £ããã¦ãã¦ããã£ã¨ã¾ã¨ãã§ãããã§ãã·ã§ãã«ãª æããååä¸ãéããã®ãæãããã詳ãããã¬ã¼ã³è³æã¯å¾æ¥å ¬éããã ãããã DELETEã®ã³ã¹ãã¯ããªãé«ã èªã¿ã ãããããå¤ãå ´åã¯ç¡å¹åã示ããã£ã¼ã«ããä½ãUPDATEãã¹ãã indexæ´æ°ã®ã³ã¹ãã馬鹿ã«ãªããªãSHOW STATUSã®è¡¨ç¤ºçµæã®è§£ææ¹æ³ èµ·åãã¨ã«åæåãå ¨ãã¼ã¿ãã¼ã¹ã«å ±érnd 㨠rnd_next ã®å²åKey_reads : Key_read_requests ããã£ã¹ã¯ããèªã¾ããåæ°ï¼ç·åæ° ãã®å²åã1:100ããæªããªã£ããè¦æ³¨æKey_write_requests:Key_writes ç·æ¸ãè¾¼ã¿è¦æ±åæ°ï¼ãã£ã¹ã¯ã«æ¸ã込㾠ããåæ° ãã£ãã·ã¥ã®å¹æãªã©Max_used_con
â ã¤ã³ããã¯ã¹ã¨ã¯ ãã¼ã¿ãã¼ã¹ã®ä¸çã§ãã¤ã³ããã¯ã¹(ç´¢å¼)ã¨ã¯ãã¼ãã«ã«æ ¼ç´ããã¦ãããã¼ã¿ã é«éã«åãåºãçºã®ä»çµã¿ãæå³ãã¾ãã ã¤ã³ããã¯ã¹ãé©åã«ä½¿ç¨ãããã¨ã«ãã£ã¦SQLæã®å¿çæéãåçã«æ¹å ãããå¯è½æ§ãããã¾ãã ã¤ã³ããã¯ã¹ã«ã¯B-Treeã¤ã³ããã¯ã¹ãã¯ãããããããããã¤ã³ããã¯ã¹ã é¢æ°ã¤ã³ããã¯ã¹ãªã©ã®ç¨®é¡ãããã¾ãããããã§ã¯æãä¸è¬çã«ä½¿ãããã㤠ã»ã¨ãã©ã®DBMSã§ãµãã¼ãããã¦ããB-Treeã¤ã³ããã¯ã¹ã«ã¤ãã¦è§£èª¬ãã¾ãã â» CREATE INDEXæã§ãªãã·ã§ã³ãæå®ããªãå ´åã¯é常B-Treeã¤ã³ããã¯ã¹ã ä½æããã¾ãã â B-Treeã¤ã³ããã¯ã¹ã®ããã¿ B-Tree(Balanced Tree)ã¤ã³ããã¯ã¹ã¯æ¬¡ã®ãããªããªã¼ç¶ã®æ§é ã«ãªã£ã¦ãã¾ãã ããªã¼ã®å é ã¯ããããããã¯ã¨å¼ã°ãã¦ãã¾ããããããããã¯ã§ã¯ããã¼å¤ã® ç¯å²
åæç¥è (explain ã®ä½¿ãæ¹) æ¼¢ (ãªãã³) ã®ã³ã³ãã¥ã¼ã¿é > MySQL ã® EXPLAIN ãå¾¹åºè§£èª¬!! ããã¥ã¢ã«(5ç³»)ã®è©²å½ç®æ MySQL 5.1 ãªãã¡ã¬ã³ã¹ããã¥ã¢ã« > 6.4 ãã¼ã¿ãã¼ã¹æ§é ã®æé©å MySQL 5.1 ãªãã¡ã¬ã³ã¹ããã¥ã¢ã« > 4.2 SELECT ã¹ãã¼ãã¡ã³ãããã³ãã®ä»ã®ã¯ã¨ãªã®æé©å MySQL 5.1 ãªãã¡ã¬ã³ã¹ããã¥ã¢ã« > 3.2.6 ã¤ã³ããã¯ã¹çµåæé©å ã¤ã³ããã¯ã¹æ¦èª¬ ã¤ã³ããã¯ã¹ã«ã¤ã㦠MySQL ã¡ã¢ MySQL ã«ã¤ãã¦ãä¼ - ã¤ã³ããã¯ã¹ã«ã¤ã㦠MySQL ã®æé©å slashdot.jpï¼ã¤ã³ããã¯ã¹ä»¥å¤ãå«ãããDBæé©åãã¨ããè¦ç¹ï¼ ã¤ã³ããã¯ã¹ã®åºç¤ç¥è åè« æ¼¢ (ãªãã³) ã®ã³ã³ãã¥ã¼ã¿é > Using filesort æ¼¢ (ãªãã³) ã®ã³ã³ãã¥ã¼ã¿é > ãªãã³ã®ã½ã¼ããã¯ã
Intro to DBIx::Class In my opinion DBIx::Class is one of the best ORM solutions out there. Not only can it model your database, including mapping out any foreign key relationships, it can also be used as a canonical point of reference for your schema.  This means we can use it not only as an application layer interface to the database, but can also define a versioned database structure using the
mysqlã§ã¯ããã©ã«ãã§ã¯NOT NULLå¶ç´ã«æ示çã«å¤ãä¸ããªãå ´åãåæã«ç©ºæåã0ã¨ãã£ãå¤ãåæã«å ¥ãã¡ããã ä¾ãã° CREATE TABLE users ( id INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY, username VARCHAR(255) NOT NULL ); ãªãã¼ãã«ã«å¯¾ã㦠INSERT INTO users(id) VALUES(1); ã¨ããããã¨ã©ã¼ã«ãªããid = 1, username = ''ã¿ãããªã¬ã³ã¼ããä½ããã¡ããã ãã§ãããã許å¯ããªãããã«ããã®ã5.0.2以ä¸ã§ãµãã¼ãããã¦ãSTRICT_ALL_TABLESã¢ã¼ããç¥ãããã£ãã§ãã SET sql_mode = 'STRICT_ALL_TABLES'; ãããã¨ã«ãã£ã¦ ERROR 1146 (42S02): Table 'u
HowFriendFeedUsesMySqlToStoreSchemaLessData - FriendFeed ã§ã¯ MySQL ã使ãã©ã®ããã«ã¹ãã¼ãã¬ã¹ã®ãã¼ã¿ãä¿åãã¦ããã®ã ç®æ¬¡ ãã®è¨äºã«ã¤ã㦠FriendFeed? ã§ã¯ MySQL ã使ãã©ã®ããã«ã¹ãã¼ãã¬ã¹ã®ãã¼ã¿ãä¿åãã¦ããã®ã èæ¯ æ¦è¦³ 詳細 ä¸è²«æ§ã¨ååæ§ æ§è½ FriendFeed? ã§ã¯ MySQL ã使ãã©ã®ããã«ã¹ãã¼ãã¬ã¹ã®ãã¼ã¿ãä¿åãã¦ããã®ã ãã®è¨äºã«ã¤ã㦠"How FriendFeed? uses MySQL to store schema-less data" ã®æ¥æ¬èªè¨³ã§ã http://bret.appspot.com/entry/how-friendfeed-uses-mysql CC 2.5 ã§ã©ã¤ã»ã³ã¹ããã¦ãã¾ã: http://creativecommons.org/
ãªãªã¼ã¹ãé害æ å ±ãªã©ã®ãµã¼ãã¹ã®ãç¥ãã
ææ°ã®äººæ°ã¨ã³ããªã¼ã®é ä¿¡
å¦çãå®è¡ä¸ã§ã
j次ã®ããã¯ãã¼ã¯
kåã®ããã¯ãã¼ã¯
lãã¨ã§èªã
eã³ã¡ã³ãä¸è¦§ãéã
oãã¼ã¸ãéã
{{#tags}}- {{label}}
{{/tags}}