Appendix聽A.聽Problems and Common Errors - MySQL 5.1参考手册中文版

瀵艰嚧鎷掔粷璁块棶閿欒��鐨勫師鍥犲緢澶氥�傝�ラ敊璇�甯镐笌杩炴帴鏃舵湇鍔″櫒鍏佽�稿�㈡埛绔�浣跨敤鐨�MySQL璐︽埛鏈夊叧銆傝�峰弬瑙�5.7.8鑺傦紝鈥滄嫆缁濊�块棶閿欒��鐨勫師鍥�鈥�銆傝�峰弬瑙�5.7.2鑺傦紝鈥滄潈闄愮郴缁熷伐浣滃師鐞嗏��銆�

Unix骞冲彴涓婄殑MySQL瀹㈡埛绔�鑳藉�熶互涓ょ�嶄笉鍚岀殑鏂瑰紡杩炴帴鍒�mysqld鏈嶅姟鍣�锛氶�氳繃鏂囦欢绯荤粺涓�鐨勬枃浠讹紙榛樿�や负/tmp/mysql.sock锛変娇鐢�Unix濂楁帴瀛楄繘琛岃繛鎺ワ紝鎴栭�氳繃绔�鍙ｅ彿浣跨敤TCP/IP杩涜�岃繛鎺ャ��Unix濂楁帴瀛楁枃浠剁殑杩炴帴閫熷害姣�TCP/IP蹇�锛屼絾浠呰兘鍦ㄤ笌鐩稿悓璁＄畻鏈轰笂鐨勬湇鍔″櫒鐩歌繛鏃朵娇鐢ㄣ�傚�傛灉鏈�鎸囧畾鎸囧畾涓绘満鍚嶆垨鎸囧畾浜嗙壒娈婄殑涓绘満鍚�localhost锛屽皢浣跨敤Unix濂楁帴瀛椼��

濡傛灉MySQL鏈嶅姟鍣ㄨ繍琛屽湪Windows 9x鎴�Me涓婏紝浠呰兘閫氳繃TCP/IP杩涜�岃繛鎺ャ�傚�傛湇鍔″櫒杩愯�屽湪Windows NT銆�2000銆�XP鎴�2003涓婏紝鑰屼笖浣跨敤--enable-named-pipe閫夐」鍚�鍔�锛屽�傛灉鍦ㄨ繍琛屾湇鍔″櫒鐨勬満鍣ㄤ笂杩愯�屽�㈡埛绔�锛屼篃鑳戒娇鐢ㄥ懡鍚嶇�￠亾杩涜�岃繛鎺ャ��榛樿�ゆ儏鍐典笅锛屽懡鍚嶇�￠亾鐨勫悕绉颁负MySQL銆傚�傛灉鍦ㄨ繛鎺ュ埌mysqld鏃舵湭缁欏畾涓绘満鍚嶏紝MySQL瀹㈡埛绔�棣栧厛浼氬皾璇曡繛鎺ュ埌鍛藉悕绠￠亾銆傚�傛灉涓嶈兘宸ヤ綔锛屽皢杩炴帴鍒�TCP/IP绔�鍙ｃ�備娇鐢ㄢ��.鈥濅綔涓轰富鏈哄悕锛屽彲鍦�Windows骞冲彴涓婂己鍒朵娇鐢ㄥ懡鍚嶇�￠亾銆�

閿欒��(2002)鈥滄棤娉曡繛鎺ュ埌鈥︹��閫氬父鎰忓懗鐫�鍦ㄧ郴缁熸病鏈夎繍琛岀殑MySQL鏈嶅姟鍣�锛屾垨鍦ㄨ繛鎺ュ埌鏈嶅姟鍣ㄦ椂浣跨敤浜嗕笉姝ｇ‘鐨�Unix濂楁帴瀛楁枃浠跺悕鎴�TCP/IP绔�鍙ｅ彿銆�

棣栧厛妫�鏌ユ湇鍔″櫒涓绘満涓婃槸鍚︽湁鍚嶄负mysqld鐨勮繘绋嬶紙鍦�Unix骞冲彴涓婁娇鐢�ps xa | grep mysqld锛屾垨鍦�Windows骞冲彴涓婁娇鐢ㄤ换鍔＄�＄悊鍣�锛夈�傚�傛灉娌℃湁杩欑被杩涚▼锛屽簲鍚�鍔ㄦ湇鍔″櫒銆傝�峰弬瑙�2.9.2.3鑺傦紝鈥滃惎鍔∕ySQL鏈嶅姟鍣ㄤ互鍙婂叾鏁呴殰璇婃柇鍜屾帓闄も��銆�

濡傛灉mysqld杩涚▼姝ｅ湪杩愯�岋紝鍙�浣跨敤涓嬭堪鍛戒护妫�鏌ャ�傚湪浣犵殑鍏蜂綋璁剧疆涓�锛岀��鍙ｅ彿鎴�Unix濂楁帴瀛楁枃浠跺悕鍙�鑳戒細鏈夋墍涓嶅悓銆�host_ip浠ｈ〃杩愯�屾湇鍔″櫒鐨勬満鍣ㄧ殑IP缂栧彿銆�

shell> mysqladmin version

shell> mysqladmin variables

shell> mysqladmin -h `hostname` version variables

shell> mysqladmin -h `hostname` --port=3306 version

shell> mysqladmin -h host_ip version

shell> mysqladmin --protocol=socket --socket=/tmp/mysql.sock version

娉ㄦ剰锛屽簲涓庝富鏈哄悕鍛戒护涓�璧蜂娇鐢ㄢ��`鈥濊�屼笉鏄�鈥溾�欌�濓紝杩欎細浣夸富鏈哄悕杈撳嚭锛堝綋鍓嶄富鏈哄悕锛夎��浠ｅ叆mysqladmin鍛戒护銆傚�傛灉娌℃湁涓绘満鍚嶅懡浠ゆ垨姝ｈ繍琛屽湪Windows骞冲彴涓婏紝搴斾互鎵嬪姩鏂瑰紡杈撳叆鏈哄櫒鐨勪富鏈哄悕锛堟棤鈥�`鈥濈�﹀彿锛夛紝鍚庤窡-h閫夐」銆�涔熷彲浠ヤ娇鐢�TCP/IP鍗忚��鐢�-h 127.0.0.1杩炴帴鍒版湰鍦颁富鏈恒��

涓嬮潰缁欏嚭浜嗕竴浜涒�滄棤娉曡繛鎺ュ埌鏈�鍦�MySQL鏈嶅姟鍣ㄢ�濋敊璇�鐨勫彲鑳藉師鍥狅細

1.    Mysqld鏈�杩愯�屻�傝�锋��鏌ユ搷浣滅郴缁熺殑杩涚▼鍒楄〃浠ョ‘淇�mysqld杩涚▼姝ｅ湪杩愯�屻��

2.    浣犳�ｅ湪鍏锋湁寰堝��TCP/IP杩炴帴鐨�Windows骞冲彴涓婅繍琛�MySQL鏈嶅姟鍣ㄣ�傚�傛灉浣犵殑瀹㈡埛绔�缁忓父鍑虹幇閿欒��锛岃�峰弬瑙�A.2.2.1鑺傦紝鈥滃湪Windows涓婁笌MySQL鏈嶅姟鍣ㄧ殑杩炴帴澶辫触鈥�锛屼互鎵惧嚭瑙勯伩鏂规硶銆�

3.    浣犳�ｅ湪浣跨敤MIT-pthreads鐨勭郴缁熶笂杩愯�屻�傚�傛灉浣犳�ｅ湪杩愯�屼笉鍏锋湁鍥烘湁绾跨▼鐨勬搷浣滅郴缁燂紝mysqld灏嗕娇鐢�MIT-pthreads杞�浠跺寘銆傝�峰弬瑙�2.1.1鑺傦紝鈥淢ySQL鏀�鎸佺殑鎿嶄綔绯荤粺鈥�銆備絾鏄�锛屽苟闈炴墍鏈夌殑MIT-pthreads鐗堟湰鍧囨敮鎸�Unix濂楁帴瀛楁枃浠躲�傚湪涓嶆敮鎸佸�楁帴瀛楁枃浠剁殑绯荤粺涓婏紝杩炴帴鍒版湇鍔″櫒鏃讹紝蹇呴』鏄庣‘鎸囧畾涓绘満鍚嶃�傝�蜂娇鐢ㄤ笅杩板懡浠ゆ潵妫�鏌ユ槸鍚﹁繛鎺ュ埌浜嗘湇鍔″櫒锛�

4.           shell> mysqladmin -h `hostname` version

5.    鏌愪汉绉诲姩浜�mysqld浣跨敤鐨�Unix濂楁帴瀛楁枃浠讹紙榛樿�や负/tmp/mysql.sock锛夈�備緥濡傦紝浣犲彲鑳芥墽琛屼簡灏嗘棫鏂囦欢浠�/tmp鐩�褰曞垹闄ょ殑cron浠诲姟銆備綘鎬昏兘鎵ц��mysqladmin version鏉ユ��鏌�mysqladmin璇曞浘浣跨敤鐨�Unix濂楁帴瀛楁枃浠舵槸鍚︾殑纭�瀛樺湪銆傚湪璇ユ儏鍐典笅锛屾洿姝ｆ柟寮忔槸鏇存敼cron浠诲姟锛屼笉鍒犻櫎mysql.sock鏂囦欢锛屾垨灏嗗�楁帴瀛楁枃浠剁疆浜庡叾浠栧湴鏂广��璇峰弬瑙�A.4.5鑺傦紝鈥滃�備綍淇濇姢鎴栨洿鏀筂ySQL濂楁帴瀛楁枃浠�/tmp/mysql.sock鈥�銆�

6.    浣犱娇鐢�--socket=/path/to/socket閫夐」鍚�鍔ㄤ簡mysqld鏈嶅姟鍣�锛屽綋蹇樿�板皢濂楁帴瀛楁枃浠剁殑鏂板悕绉伴�氱煡瀹㈡埛绔�绋嬪簭銆傚�傛灉鏇存敼浜嗗叧浜庢湇鍔″櫒鐨勫�楁帴瀛楄矾寰勶紝涔熷繀椤婚�氱煡MySQL瀹㈡埛绔�銆傚彲鍦ㄨ繍琛屽�㈡埛绔�绋嬪簭鏃朵娇鐢ㄧ浉鍚岀殑鈥攕ocket閫夐」鏉ュ畬鎴愯�ヤ换鍔°�傛�ゅ�栵紝浣犺繕搴旂‘淇濆�㈡埛绔�鍏锋湁璁块棶鏂囦欢mysql.sock鐨勬潈闄愩�傝�佹兂鎵惧嚭濂楁帴瀛楁枃浠剁殑浣嶇疆锛屽彲浣跨敤锛�

7.           shell> netstat -ln | grep mysql

璇峰弬瑙�A.4.5鑺傦紝鈥滃�備綍淇濇姢鎴栨洿鏀筂ySQL濂楁帴瀛楁枃浠�/tmp/mysql.sock鈥�銆�

8.    浣犳�ｅ湪浣跨敤Linux鑰屼笖1涓�鏈嶅姟鍣ㄧ嚎绋嬪凡姝讳骸锛堝唴鏍稿凡娓呴櫎锛夈�傚湪姝ゆ儏鍐典笅锛屽湪閲嶅惎MySQL鏈嶅姟鍣ㄤ箣鍓嶏紝蹇呴』鏉�姝诲叾浠�mysqld绾跨▼锛堜緥濡傦紝浣跨敤kill鎴�mysql_zap鑴氭湰锛夈��璇峰弬瑙�A.4.2鑺傦紝鈥滃�傛灉MySQL渚濈劧宕╂簝锛屽簲浣滀簺浠�涔堚��銆�

9.    鏈嶅姟鍣ㄦ垨瀹㈡埛绔�绋嬪簭涓嶅叿鏈夎�块棶鍖呭惈Unix濂楁帴瀛楁枃浠剁殑鐩�褰曟垨濂楁帴瀛楁枃浠舵湰韬�鐨勬伆褰撴潈闄愩�傚湪璇ユ儏鍐典笅锛屽繀椤绘洿鏀圭洰褰曟垨濂楁帴瀛楁枃浠剁殑璁块棶鏉冮檺锛屼互渚挎湇鍔″櫒鎴栧�㈡埛绔�绋嬪簭鑳藉�熻�块棶瀹冧滑锛屾垨鐢�鈥搒ocket閫夐」閲嶅惎mysqld锛屽湪璇ラ�夐」涓�鎸囧畾鏈嶅姟鍣ㄨ兘鍒涘缓銆佽�屼笖瀹㈡埛绔�鍙�璁块棶鐨勭洰褰曚笅鐨勫�楁帴瀛楁枃浠跺悕銆�

濡傛灉閬囧埌閿欒��娑堟伅鈥滄棤娉曡繛鎺ュ埌some_host涓婄殑MySQL鏈嶅姟鍣�鈥濓紝鍙�灏濊瘯閲囧彇涓嬭堪姝ラ�や互鎵惧嚭闂�棰樻墍鍦�锛�

路         鎵ц�屸��telnet some_host 3306鈥�骞舵寜涓ゆ�″洖杞﹂敭锛屾��鏌ユ湇鍔″櫒鏄�鍚﹁繍琛屽湪璇ヤ富鏈轰笂锛�3306鏄�榛樿�ょ殑MySQL绔�鍙ｅ彿銆傚�傛灉浣犵殑鏈嶅姟鍣ㄦ�ｅ湪鐩戝惉涓嶅悓鐨勭��鍙ｏ紝璇锋洿鏀硅�ュ�硷級銆傚�傛灉鏈�1涓�MySQL鏈嶅姟鍣ㄦ�ｅ湪杩愯�屽苟鐩戝惉璇ョ��鍙ｏ紝浣犲簲鏀跺埌鍖呭惈鏈嶅姟鍣ㄧ増鏈�鍙风殑鍥炲簲銆傚�傛灉閬囧埌閿欒��锛屽�傗��telnet:鏃犳硶杩炴帴鍒拌繙绋嬩富鏈�:鎷掔粷杩炴帴鈥�锛岃〃绀哄湪璇ュ畾绔�鍙ｄ笂娌℃湁杩愯�岀殑鏈嶅姟鍣ㄣ��

路         濡傛灉鏈嶅姟鍣ㄦ�ｈ繍琛屽湪鏈�鍦颁富鏈轰笂锛岃�蜂娇鐢�Unix濂楁帴瀛楁枃浠讹紝骞朵娇鐢�mysqladmin -h localhost variables杩涜�岃繛鎺ャ�傞獙璇佹湇鍔″櫒鐩戝惉鐨�TCP/IP绔�鍙ｅ彿锛堝畠鏄�port鍙橀噺鐨勫�硷級銆�

路         纭�淇濅綘鐨�mysqld鏈嶅姟鍣ㄦ湭鐢�--skip-networking閫夐」鍚�鍔ㄣ��濡傛灉浣跨敤浜嗚�ラ�夐」锛屽皢鏃犳硶浣跨敤TCP/IP杩炴帴鍒板畠銆�

路         妫�鏌ュ苟纭�璁や笉瀛樺湪灞忚斀浜嗗��MySQL璁块棶鐨勯槻鐏�澧欍�傞渶瑕侀厤缃�璇稿��ZoneAlarm鍜�Windows XP涓�浜洪槻鐏�澧欑瓑搴旂敤绋嬪簭锛屼互鍏佽�稿��MySQL鏈嶅姟鍣ㄧ殑澶栭儴璁块棶銆�

路                HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

路                Value Name: MaxUserPort

路                Data Type: REG_DWORD

路                Value: 65534

路                Value Name: TcpTimedWaitDelay

路                Data Type: REG_DWORD

路                Value: 30

MySQL 5.1閲囩敤浜嗗熀浜庡瘑鐮佹贩缂栫畻娉曠殑閴村畾鍗忚��锛屽畠涓庢棭鏈熷�㈡埛绔�锛�4.1涔嬪墠锛変娇鐢ㄧ殑鍗忚��涓嶅吋瀹广�傚�傛灉浣犲皢鏈嶅姟鍣ㄥ崌绾у埌4.1涔嬩笂锛岀敤鏃╂湡鐨勫�㈡埛绔�杩涜�岃繛鎺ュ彲鑳藉け璐ワ紝骞剁粰鍑轰笅杩版秷鎭�锛�

shell> mysql

瀹㈡埛绔�涓嶆敮鎸佹湇鍔″櫒璇锋眰鐨勯壌瀹氬崗璁�锛氳�疯�冭檻鍗囩骇MySQL瀹㈡埛绔�銆�

瑕佹兂瑙ｅ喅璇ラ棶棰橈紝搴斾娇鐢ㄤ笅杩版柟娉曚箣涓�锛�

路         鍗囩骇鎵�鏈夌殑瀹㈡埛绔�绋嬪簭锛屼互浣跨敤4.1.1鎴栨洿鏂扮殑瀹㈡埛绔�搴撱��

路         鐢�4.1鐗堜箣鍓嶇殑瀹㈡埛绔�杩炴帴鍒版湇鍔″櫒鏃讹紝璇蜂娇鐢ㄤ粛鍏锋湁4.1鐗堜箣鍓嶉�庢牸瀵嗙爜鐨勮处鎴枫��

路         瀵逛簬闇�瑕佷娇鐢�4.1鐗堜箣鍓嶇殑瀹㈡埛绔�鐨勬瘡浣嶇敤鎴凤紝灏嗗瘑鐮佹仮澶嶄负4.1鐗堜箣鍓嶇殑椋庢牸銆傚彲浠ヤ娇鐢�SET PASSWORD璇�鍙ュ拰OLD_PASSWORD()鍑芥暟瀹屾垚璇ヤ换鍔★細

路                mysql> SET PASSWORD FOR

路                    -> 'some_user'@'some_host' = OLD_PASSWORD('newpwd');

涔熷彲浠ヤ娇鐢�UPDATE鍜�FLUSH PRIVILEGES锛�

mysql> UPDATE mysql.user SET Password = OLD_PASSWORD('newpwd')

    -> WHERE Host = 'some_host' AND User = 'some_user';

mysql> FLUSH PRIVILEGES;

鐢ㄤ綘鎵撶畻浣跨敤鐨勫瘑鐮佹浛鎹㈠墠渚嬩腑鐨勨��newpwd鈥濄��MySQL涓嶈兘鍛婅瘔浣犲師鏉ョ殑瀵嗙爜鏄�浠�涔堬紝鍥犳�わ紝浣犻渶瑕侀�夋嫨鏂扮殑瀵嗙爜銆�

路         閫氱煡鏈嶅姟鍣ㄤ娇鐢ㄦ棫鐨勫瘑鐮佹贩缂栫畻娉曪細

1.    浣跨敤鈥�--old-passwords鈥濋�夐」鍚�鍔�mysqld銆�

2.    瀵逛簬宸插皢瀵嗙爜鏇存柊涓鸿緝闀�4.1鏍煎紡鐨勬瘡涓�璐︽埛锛屼负鍏舵寚瀹氬叿鏈夋棫鏍煎紡鐨勫瘑鐮併�傚彲浠ヤ娇鐢ㄤ笅杩版煡璇㈢‘瀹氳繖浜涜处鎴凤細

3.                 mysql> SELECT Host, User, Password FROM mysql.user

4.                     -> WHERE LENGTH(Password) > 16;

瀵逛簬鏌ヨ�㈡樉绀虹殑姣忎釜璐︽埛璁板綍锛岃�蜂娇鐢�Host鍜�User鍊硷紝骞朵娇鐢�OLD_PASSWORD()鍑芥暟浠ュ強SET PASSWORD鎴�UPDATE涔嬩竴鎸囧畾瀵嗙爜锛屽�傚墠闈㈡墍浠嬬粛鐨勯偅鏍枫��

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shell> mysql -u user_name -p

Enter password:

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shell> mysqld_safe --max_connect_errors=10000 &

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mysqld瀹為檯涓婂厑璁�max_connections+1涓�瀹㈡埛绔�杩涜�岃繛鎺ャ��棰濆�栫殑杩炴帴淇濈暀缁欏叿鏈�SUPER鏉冮檺鐨勮处鎴枫�傞�氳繃涓虹郴缁熺�＄悊鍛樿�屼笉鏄�鏅�閫氱敤鎴锋巿浜�SUPER鏉冮檺锛堟櫘閫氱敤鎴蜂笉搴斿叿鏈夎�ユ潈闄愶級锛岀郴缁熺�＄悊鍛樿兘澶熻繛鎺ュ埌鏈嶅姟鍣�锛�骞朵娇鐢�SHOW PROCESSLIST鏉ヨ瘖鏂�闂�棰橈紝鍗充娇宸茶繛鎺ョ殑鏃犵壒鏉冨�㈡埛绔�鏁板凡杈惧埌鏈�澶у�间篃鍚屾牱銆�璇峰弬瑙�13.5.4.16鑺傦紝鈥淪HOW PROCESSLIST璇�娉曗��銆�

MySQL鑳芥敮鎸佺殑鏈�澶ц繛鎺ユ暟鍙栧喅浜庣粰瀹氬钩鍙颁笂绾跨▼搴撶殑璐ㄩ噺銆�Linux鎴�Solaris搴旇兘鏀�鎸�500-1000涓�骞跺彂杩炴帴锛屽叿浣撴儏鍐靛彇鍐充簬RAM瀹归噺锛屼互鍙婂�㈡埛绔�姝ｅ湪浣滀粈涔堛��MySQL AB鎻愪緵鐨勯潤鎬�Linux搴撹兘鏀�鎸侀珮杈�4000涓�杩炴帴銆�

濡傛灉浣跨敤mysql瀹㈡埛绔�绋嬪簭鍙戝嚭浜嗘煡璇�锛屽苟鏀跺埌涓嬭堪閿欒��涔嬩竴锛屽垯琛ㄧずmysql娌℃湁瓒冲�熷唴瀛樻潵淇濆瓨鍏ㄩ儴鏌ヨ�㈢粨鏋滐細

mysql: Out of memory at line 42, 'malloc.c'

mysql: needed 8136 byte (8k), memory in use: 12481367 bytes (12189k)

閿欒��2008: MySQL client ran out of memory

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鍦ㄦ湰鑺備腑锛岃繕浠嬬粛浜嗗嚭鐜版煡璇㈤敊璇�鏈熼棿锛屼笌涓㈠け浜嗘湇鍔″櫒杩炴帴鏈夊叧鐨勪簨瀹溿��

MySQL鏈嶅姟鍣ㄤ笉鍙�鐢ㄩ敊璇�鐨勬渶甯歌�佸師鍥犳槸鏈嶅姟鍣ㄨ秴鏃朵互鍙婅繛鎺ュ凡鍏抽棴銆傚湪璇ユ儏鍐典笅锛岄�氬父鑳借�佸埌涓嬭堪閿欒��浠ｇ爜涔嬩竴锛堝叿浣撶殑閿欒��浠ｇ爜涓庢搷浣滅郴缁熸湁鍏筹級锛�

鍦ㄩ粯璁ゆ儏鍐典笅锛屽�傛灉鏈�鍙戠敓浠讳綍浜嬶紝8灏忔椂鍚庢湇鍔″櫒灏嗗叧闂�杩炴帴銆備篃鍙�浠ュ湪鍚�鍔�mysqld鏃讹紝閫氳繃璁剧疆wait_timeout鍙橀噺鏇存敼鏃堕棿闄愬埗銆傝�峰弬瑙�5.3.3鑺傦紝鈥滄湇鍔″櫒绯荤粺鍙橀噺鈥�.

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路         濡傛灉MySQL鏄�鐢ㄢ��--skip-networking鈥濋�夐」鍚�鍔ㄧ殑锛屼篃浼氳�佸埌MySQL鏈嶅姟鍣ㄤ笉鍙�鐢ㄩ敊璇�銆�

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2.    濡傛灉鐗瑰畾鏌ヨ�㈡潃姝讳簡mysqld锛岃�屼笖鍦ㄨ繍琛屾煡璇㈠墠鐢�CHECK TABLE妫�鏌ヤ簡娑夊強鐨勮〃锛屼綘鏄�鍚﹁兘鎻愪緵鍙�閲嶅�嶇殑娴嬭瘯鑼冧緥锛�璇峰弬瑙�E.1.6鑺傦紝鈥滃�傛灉鍑虹幇琛ㄥ穿婧冿紝璇风敓鎴愭祴璇曟�堜緥鈥�銆�

3.    鍦�MySQL鏈嶅姟鍣ㄤ腑锛岀郴缁熷彉閲�wait_timeout鐨勫�兼槸浠�涔堬紵锛�mysqladmin variables缁欏嚭浜嗚�ュ彉閲忕殑鍊硷級銆�

4.    浣犳槸鍚﹀皾璇曚娇鐢ㄢ��--log鈥濋�夐」鏉ヨ繍琛�mysqld锛屼互纭�瀹氭槸鍚﹀湪鏃ュ織涓�鍑虹幇闂�棰橈紵

鍙﹁�峰弬瑙�A.2.10鑺傦紝鈥滈�氫俊閿欒��鍜屽け鏁堣繛鎺モ��銆�

璇峰弬瑙�1.7.1.2鑺傦紝鈥滆�锋暀闂�棰樻垨閫氭姤缂洪櫡鈥�銆�

閫氫俊淇℃伅鍖呮槸鍙戦�佽嚦MySQL鏈嶅姟鍣ㄧ殑鍗曚釜SQL璇�鍙ワ紝鎴栧彂閫佽嚦瀹㈡埛绔�鐨勫崟涓�琛屻��

鍦�MySQL 5.1鏈嶅姟鍣ㄥ拰瀹㈡埛绔�涔嬮棿鏈�澶ц兘鍙戦�佺殑鍙�鑳戒俊鎭�鍖呬负1GB銆�

褰�MySQL瀹㈡埛绔�鎴�mysqld鏈嶅姟鍣ㄦ敹鍒板ぇ浜�max_allowed_packet瀛楄妭鐨勪俊鎭�鍖呮椂锛屽皢鍙戝嚭鈥�淇℃伅鍖呰繃澶�鈥�閿欒��锛屽苟鍏抽棴杩炴帴銆傚�逛簬鏌愪簺瀹㈡埛绔�锛屽�傛灉閫氫俊淇℃伅鍖呰繃澶э紝鍦ㄦ墽琛屾煡璇㈡湡闂达紝浜嗚兘鍥為亣鍒�鈥�涓㈠け涓�MySQL鏈嶅姟鍣ㄧ殑杩炴帴鈥�閿欒��銆�

瀹㈡埛绔�鍜屾湇鍔″櫒鍧囨湁鑷�宸辩殑max_allowed_packet鍙橀噺锛�鍥犳�わ紝濡備綘鎵撶畻澶勭悊澶х殑淇℃伅鍖咃紝蹇呴』澧炲姞瀹㈡埛绔�鍜屾湇鍔″櫒涓婄殑璇ュ彉閲忋��

濡傛灉浣犳�ｅ湪浣跨敤mysql瀹㈡埛绔�绋嬪簭锛屽叾max_allowed_packet鍙橀噺鐨勯粯璁ゅ�间负16MB銆傝�佹兂璁剧疆杈冨ぇ鐨勫�硷紝鍙�鐢ㄤ笅杩版柟寮忓惎鍔�mysql锛�

mysql> mysql --max_allowed_packet=32M

瀹冨皢淇℃伅鍖呯殑澶у皬璁剧疆涓�32MB銆�

鏈嶅姟鍣ㄧ殑榛樿��max_allowed_packet鍊间负1MB銆傚�傛灉鏈嶅姟鍣ㄩ渶瑕佸�勭悊澶х殑鏌ヨ��锛屽彲澧炲姞璇ュ�硷紙渚嬪�傦紝濡傛灉鍑嗗�囧�勭悊澶х殑BLOB鍒楋級銆備緥濡傦紝瑕佹兂灏嗚�ヨ�剧疆涓�16MB锛屽彲閲囩敤涓嬭堪鏂瑰紡鍚�鍔ㄦ湇鍔″櫒锛�

mysql> mysqld --max_allowed_packet=16M

涔熻兘浣跨敤閫夐」鏂囦欢鏉ヨ�剧疆max_allowed_packet銆�瑕佹兂灏嗘湇鍔″櫒鐨勮�ュ彉閲忚�剧疆涓�16MB锛屽彲鍦ㄩ�夐」鏂囦欢涓�澧炲姞涓嬭�屽唴瀹癸細

[mysqld]

max_allowed_packet=16M

澧炲姞璇ュ彉閲忕殑鍊煎崄鍒嗗畨鍏�锛岃繖鏄�鍥犱负浠呭綋闇�瑕佹椂鎵嶄細鍒嗛厤棰濆�栧唴瀛樸�備緥濡傦紝浠呭綋浣犲彂鍑洪暱鏌ヨ�㈡垨mysqld蹇呴』杩斿洖澶х殑缁撴灉琛屾椂mysqld鎵嶄細鍒嗛厤鏇村�氬唴瀛樸�傝�ュ彉閲忎箣鎵�浠ュ彇杈冨皬榛樿�ゅ�兼槸涓�绉嶉�勯槻鎺�鏂斤紝浠ユ崟鑾峰�㈡埛绔�鍜屾湇鍔″櫒涔嬮棿鐨勯敊璇�淇℃伅鍖咃紝骞剁‘淇濅笉浼氬洜鍋剁劧浣跨敤澶х殑淇℃伅鍖呰�屽�艰嚧鍐呭瓨婧㈠嚭銆�

濡傛灉浣犳�ｆ槸鐢ㄥぇ鐨�BLOB鍊硷紝鑰屼笖鏈�涓�mysqld鎺堜簣涓哄�勭悊鏌ヨ�㈣�岃�块棶瓒冲�熷唴瀛樼殑鏉冮檺锛屼篃浼氶亣鍒颁笌澶т俊鎭�鍖呮湁鍏崇殑濂囨��闂�棰樸�傚�傛灉鎬�鐤戝嚭鐜颁簡璇ユ儏鍐碉紝璇峰皾璇曞湪mysqld_safe鑴氭湰寮�濮嬪�炲姞ulimit -d 256000锛屽苟閲嶅惎mysqld銆�

瀵逛簬杩炴帴闂�棰橈紝鏈嶅姟鍣ㄩ敊璇�鏃ュ織鏄�鏈夌敤鐨勪俊鎭�婧愩�傝�峰弬瑙�5.11.1鑺傦紝鈥滈敊璇�鏃ュ織鈥�銆傚�傛灉鏈嶅姟鍣ㄦ槸鐢ㄢ��--log-warnings鈥濋�夐」鍚�鍔ㄧ殑锛屽湪閿欒��鏃ュ織涓�鍙�鑳戒細鍙戠幇涓嬭堪娑堟伅锛�

010301 14:38:23  Aborted connection 854 to db: 'users' user: 'josh'

濡傛灉鈥�Aborted connections鈥�锛堟斁寮冭繛鎺ワ級娑堟伅鍑虹幇鍦ㄩ敊璇�鏃ュ織涓�锛屽彲鑳界殑鍘熷洜鏄�锛�

1.    瀹㈡埛绔�绋嬪簭鍦ㄩ��鍑轰箣鍓嶆湭璋冪敤mysql_close()銆�

2.    瀹㈡埛绔�鐨勭┖闂叉椂闂磋秴杩�wait_timeout鎴�interactive_timeout绉掞紝鏈�鍚戞湇鍔″櫒鍙戝嚭浠讳綍璇锋眰銆�璇峰弬瑙�5.3.3鑺傦紝鈥滄湇鍔″櫒绯荤粺鍙橀噺鈥�銆�

3.    瀹㈡埛绔�鍦ㄦ暟鎹�浼犺緭涓�閫旂獊鐒剁粨鏉熴��

鍑虹幇杩欑被鎯呭喌鏃讹紝鏈嶅姟鍣ㄥ皢澧炲姞鈥�Aborted_clients鈥�锛堟斁寮冨�㈡埛绔�锛夌姸鎬佸彉閲忋��

鍑虹幇涓嬭堪鎯呭喌鏃讹紝鏈嶅姟鍣ㄥ皢澧炲姞鈥�Aborted_clients鈥�锛堟斁寮冨�㈡埛绔�锛夌姸鎬佸彉閲忋��

路         瀹㈡埛绔�涓嶅叿鏈夎繛鎺ヨ嚦鏁版嵁搴撶殑鏉冮檺銆�

路         瀹㈡埛绔�閲囩敤浜嗕笉姝ｇ‘鐨勫瘑鐮併��

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路         鑾峰彇杩炴帴淇℃伅鍖呯殑鏃堕棿瓒呰繃connect_timeout绉掋��璇峰弬瑙�5.3.3鑺傦紝鈥滄湇鍔″櫒绯荤粺鍙橀噺鈥�銆�

濡傛灉鍑虹幇杩欑被鎯呭喌锛屽彲鑳借〃鏄庢煇浜烘�ｈ瘯鍥句镜鍏ヤ綘鐨勬湇鍔″櫒锛�

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路         涓�Linux涓�璧蜂娇鐢ㄤ互澶�缃戝崗璁�锛屽崐鍙屽伐鎴栧叏鍙屽伐銆傚緢澶�Linux浠ュお缃戦┍鍔ㄥ潎瀛樺湪璇ョ己闄枫�傚簲閫氳繃FTP鍦ㄥ�㈡埛绔�鍜屾湇鍔″櫒鏈哄櫒涔嬮棿浼犺緭澶ф枃浠舵潵娴嬭瘯璇ョ己闄枫�傚�傛灉浼犺緭澶勪簬burst-pause-burst-pause锛堢垎鍙�-鏆傚仠-鐖嗗彂-鏆傚仠锛夋ā寮忥紝琛ㄦ槑浣犻亣鍒颁簡Linux鍙屽伐鏁呴殰銆傚敮涓�鐨勮В鍐虫柟娉曟槸锛屽皢缃戝崱鍜�Hub/浜ゆ崲鍣ㄧ殑鍙屽伐妯″紡鍒囨崲涓哄叏鍙屽伐鎴栧崐鍙屽伐锛屽苟瀵圭粨鏋滆繘琛屾祴璇曚互纭�瀹氭渶浣宠�剧疆銆�

路         涓庣嚎绋嬪簱鏈夊叧鐨勬煇浜涢棶棰樺�艰嚧璇诲彇涓�鏂�銆�

路         閰嶇疆涓嶈壇鐨�TCP/IP銆�

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路         鍙橀噺max_allowed_packet杩囧皬鎴�鏌ヨ�㈣�佹眰鐨勫唴瀛樿秴杩囦负mysqld鍒嗛厤鐨勫唴瀛樸�傝�峰弬瑙�A.2.9鑺傦紝鈥滀俊鎭�鍖呰繃澶р��銆�

鍙﹁�峰弬瑙�A.2.8鑺傦紝鈥淢ySQL鏈嶅姟鍣ㄤ笉鍙�鐢ㄢ��銆�

琛ㄥ凡婊￠敊璇�鍑虹幇鐨勬柟寮忔湁鏁扮�嶏細

路         浣犳�ｅ湪浣跨敤浣庝簬3.23鐗堢殑MySQL鏈嶅姟鍣�锛岃�屼笖鈥滃唴瀛樹腑鈥濅复鏃惰〃瓒呰繃浜�tmp_table_size瀛楄妭銆�瑕佹兂閬垮厤璇ラ棶棰橈紝鍙�浣跨敤鈥�-O tmp_table_size=val鈥濋�夐」浠ヤ究mysqld澧炲姞涓存椂琛ㄧ殑澶у皬锛屾垨鍦ㄥ彂鍑烘湁闂�棰樼殑鏌ヨ��涔嬪墠锛屼娇鐢�SQL閫夐」SQL_BIG_TABLES銆�璇峰弬瑙�13.5.3鑺傦紝鈥淪ET璇�娉曗��銆�

涔熷彲浠ヤ娇鐢ㄢ��--big-tables鈥濋�夐」鍚�鍔�mysqld銆傚畠涓庝娇鐢ㄩ拡瀵规墍鏈夋煡璇㈢殑SQL_BIG_TABLES瀹屽叏鐩稿悓銆�

鑷�MySQL 3.23璧凤紝璇ラ棶棰樺簲涓嶅啀鍑虹幇銆傚�傛灉鈥滃唴瀛樹腑鈥濅复鏃惰〃瓒呰繃tmp_table_size锛屾湇鍔″櫒浼氳嚜鍔ㄥ皢鍏惰浆鎹�涓哄熀浜庣�佺洏鐨�MyISAM琛ㄣ��

路         浣犳�ｅ湪浣跨敤InnoDB琛�锛�骞惰秴鍑轰簡InnoDB琛ㄧ┖闂淬��鍦ㄨ�ユ儏鍐典笅锛岃В鍐虫柟娉曟槸澧炲姞InnoDB琛ㄧ┖闂淬�傝�峰弬瑙�15.2.7鑺傦紝鈥滄坊鍔犲拰鍒犻櫎InnoDB鏁版嵁鍜屾棩蹇楁枃浠�鈥�銆�

路         浣犳�ｅ湪浠呮敮鎸�2GB鏂囦欢鐨勬搷浣滅郴缁熶笂浣跨敤ISAM鎴�MyISAM琛�锛屾暟鎹�鏂囦欢鎴栫储寮曟枃浠惰揪鍒颁簡璇ラ檺鍒跺�笺��

路         浣犳�ｅ湪浣跨敤MyISAM琛�锛岃�屼笖琛ㄦ墍闇�鐨勭┖闂磋秴杩囧唴閮ㄦ寚閽堝厑璁哥殑澶у皬銆傚�傛灉鍦ㄥ垱寤鸿〃鏃舵湭鎸囧畾MAX_ROWS琛�锛�MySQL灏嗕娇鐢�myisam_data_pointer_size绯荤粺鍙橀噺銆�榛樿�ゅ�间负6瀛楄妭锛屽畠瓒充互瀹圭撼65536TB鏁版嵁銆傝�峰弬瑙�5.3.3鑺傦紝鈥滄湇鍔″櫒绯荤粺鍙橀噺鈥�銆�

浣跨敤璇ヨ��鍙ワ紝鍙�妫�鏌ユ渶澶ф暟鎹�/绱㈠紩澶у皬锛�

SHOW TABLE STATUS FROM database LIKE 'tbl_name';

涔熷彲浠ヤ娇鐢�myisamchk -dv /path/to/table-index-file銆�

濡傛灉鎸囬拡澶у皬杩囧皬锛屽彲浣跨敤ALTER TABLE鏇存�ｈ�ラ棶棰橈細

ALTER TABLE tbl_name MAX_ROWS=1000000000 AVG_ROW_LENGTH=nnn;

浠呭簲涓哄叿鏈�BLOB鎴�TEXT鍒楃殑琛ㄦ寚瀹�AVG_ROW_LENGTH銆�鍦ㄨ�ユ儏鍐典笅锛�MySQL涓嶈兘浠呮牴鎹�琛屾暟浼樺寲鎵�闇�鐨勭┖闂淬��

濡傛灉瀵规煇浜涙煡璇㈤亣鍒颁笅杩扮被鍨嬬殑閿欒��锛屽畠鎰忓懗鐫�MySQL涓嶈兘涓轰复鏃剁洰褰曚笅鐨勭粨鏋滈泦鍒涘缓涓存椂鏂囦欢锛�

鏃犳硶鍒涘缓/鍐欏叆鏂囦欢'\\sqla3fe_0.ism'銆�

鍓嶈堪閿欒��鏄�Windows骞冲彴涓婄殑鍏稿瀷娑堟伅锛�Unix骞冲彴涓婄殑娑堟伅涓庝箣绫讳技銆�

涓�绉嶆洿姝ｆ柟寮忔槸浣跨敤鈥�--tmpdir鈥濋�夐」鍚�鍔�mysqld锛屾垨鍦ㄩ�夐」鏂囦欢鐨�[mysqld]閮ㄥ垎澧炲姞璇ラ�夐」銆�渚嬪�傦紝瑕佹兂鎸囧畾鐩�褰�C:\temp锛屽彲浣跨敤锛�

[mysqld]

tmpdir=C:/temp

鐩�褰�C:\temp蹇呴』瀛樺湪锛�骞舵湁瓒冲�熺殑绌洪棿鍏佽��MySQL鍐欏叆瀹冦�傝�峰弬瑙�4.3.2鑺傦紝鈥滀娇鐢ㄩ�夐」鏂囦欢鈥�銆�

璇ラ敊璇�鐨勫彟涓�涓�鍘熷洜鍙�鑳芥槸璁稿彲浜嬪疁銆傝�风‘璁�MySQL鏈嶅姟鍣ㄨ兘澶熷啓鍏�tmpdir鐩�褰曘��

姝ゅ�栵紝杩樼敤浣跨敤perror妫�鏌ラ敊璇�浠ｇ爜銆傛湇鍔″櫒鏃犳硶鍐欏叆琛ㄧ殑涓�涓�鍘熷洜鏄�鏂囦欢绯荤粺宸叉弧銆�

shell> perror 28

閿欒��浠ｇ爜28锛氱�佺洏涓婃棤鍓╀綑绌洪棿銆�

濡傛灉閬囧埌涓嬭堪閿欒��锛岃〃绀哄綋鍚�鍔�mysqld鏃舵垨閲嶆柊鍔犺浇鎺堟潈琛ㄦ椂锛屽湪鐢ㄦ埛琛ㄤ腑鍙戠幇鍏锋湁闈炴硶瀵嗙爜鐨勮处鎴枫��

鍙戠幇鐢ㄦ埛'some_user'@'some_host'瀵嗙爜閿欒��锛氬拷鐣ョ敤鎴枫��

浣滀负鍏剁粨鏋滐紝璁稿彲绯荤粺灏嗙畝鍗曞拷鐣ヨ处鎴枫��

鍦ㄤ笅闈㈢殑浠嬬粛涓�锛屾寚鏄庝簡鍙�鑳界殑鍘熷洜鍜岄棶棰樼殑鏇存�ｆ帾鏂斤細

1.    鎴栬�革紝浣犳�ｆ墦绠楃敤鏃х殑鐢ㄦ埛琛ㄨ繍琛屾柊鐗堟湰鐨�mysqld銆傛墽琛�mysqlshow mysql user妫�鏌�Password锛堝瘑鐮侊級鍒楁槸鍚︾煭浜�16涓�瀛楃�︼紝閫氳繃璇ユ柟寮忓彲妫�鏌ヨ�ラ棶棰樸�傚�傛灉缁撴灉鏄�鑲�瀹氱殑锛屽彲杩愯�岃剼鏈�/add_long_password鑴氭湰鏇存�ｈ�ラ棶棰樸��

2.    璐︽埛鍏锋湁鏃х殑瀵嗙爜锛�8瀛楃�﹂暱锛夛紝鑰屼笖鏈�浣跨敤鈥�--old-protocol鈥濋�夐」鍚�鍔�mysqld銆傛洿鏂扮敤鎴疯〃涓�鐨勮处鎴凤紝浣夸箣鍏锋湁鏂扮殑瀵嗙爜锛屾垨浣跨敤鈥�--old-protocol鈥濋�夐」閲嶅惎mysqld銆�

3.    鍦ㄧ敤鎴疯〃涓�鏈�浣跨敤PASSWORD()鍑芥暟鎸囧畾浜嗗瘑鐮併��浣跨敤mysql鐢ㄦ柊瀵嗙爜鏇存柊鐢ㄦ埛琛ㄤ腑鐨勮处鎴凤紝鍔″繀浣跨敤PASSWORD()鍑芥暟锛�

4.           mysql> UPDATE user SET Password=PASSWORD('newpwd')

5.               -> WHERE User='some_user' AND Host='some_host';

濡傛灉閬囧埌涓嬭堪閿欒��涔嬩竴锛岄�氬父鎰忓懗鐫�褰撳墠鏁版嵁搴撲腑涓嶅瓨鍦ㄥ叿鏈夌粰瀹氬悕绉扮殑琛�锛�

琛�'tbl_name'涓嶅瓨鍦�

鏃犳硶鎵惧埌鏂囦欢锛�'tbl_name' (errno: 2)

鍦ㄦ煇浜涙儏鍐典笅锛岃〃鎴栬�稿瓨鍦�锛屼絾鏈�姝ｇ‘寮曠敤瀹冿細

路         鐢变簬MySQL浣跨敤鐩�褰曞拰鏂囦欢鏉ヤ繚瀛樻暟鎹�搴撳拰琛�锛屽�傛灉瀹冧滑浣嶄簬鍖哄垎鏂囦欢鍚嶅ぇ灏忓啓鐨勬枃浠剁郴缁熶笂锛屾暟鎹�搴撳拰琛ㄥ悕涔熷尯鍒嗘枃浠跺ぇ灏忓啓銆�

路         鍗充娇瀵逛簬涓嶅尯鍒嗗ぇ灏忓啓鐨勬枃浠剁郴缁燂紝濡�Windows锛屽湪鏌ヨ�㈠唴瀵圭粰瀹氳〃鐨勬墍鏈夊紩鐢ㄥ繀椤讳娇鐢ㄧ浉鍚岀殑澶у皬鍐欍��

鍙�浠ヤ娇鐢�SHOW TABLES妫�鏌ヤ綅浜庡綋鍓嶆暟鎹�搴撲腑鐨勮〃銆傝�峰弬瑙�13.5.4鑺傦紝鈥淪HOW璇�娉曗��銆�

濡傛灉瀛樺湪瀛楃�﹂泦闂�棰橈紝鍙�鑳戒細閬囧埌涓嬭堪閿欒��锛�

MySQL杩炴帴澶辫触锛氭棤娉曞垵濮嬪寲瀛楃�﹂泦charset_name銆�

瀵艰嚧璇ラ敊璇�鐨勫師鍥狅細

路         瀛楃�﹂泦涓哄�氬瓧鑺傚瓧绗﹂泦锛屼絾瀹㈡埛绔�涓嶆敮鎸佽�ュ瓧绗﹂泦銆傚湪璇ユ儏鍐典笅锛岄渶瑕佷娇鐢ㄢ��--with-charset=charset_name鈥濇垨鈥�--with-extra-charsets=charset_name鈥濋�夐」杩愯��configure浠ラ噸鏂扮紪璇戝�㈡埛绔�銆傝�峰弬瑙�2.8.2鑺傦紝鈥滃吀鍨嬮厤缃�閫夐」鈥�銆�

鎵�鏈夌殑鏍囧噯MySQL浜岃繘鍒舵枃浠跺潎鏄�閲囩敤鈥�--with-extra-character-sets=complex鈥濈紪璇戠殑锛岃兘澶熸敮鎸佹墍鏈夌殑澶氬瓧鑺傚瓧绗﹂泦銆傝�峰弬瑙�5.10.1鑺傦紝鈥滄暟鎹�鍜屾帓搴忕敤瀛楃�﹂泦鈥�銆�

路         瀛楃�﹂泦鏄�鏈�缂栬瘧鍒�mysqld涓�鐨勭畝鍗曞瓧绗﹂泦锛岃�屼笖瀛楃�﹂泦瀹氫箟鏂囦欢涓嶅湪瀹㈡埛绔�棰勬湡鐨勪綅缃�銆�

鍦ㄨ�ユ儏鍐典笅锛岄渶瑕侀噰鍙栦笅杩版柟娉曚箣涓�瑙ｅ喅闂�棰橈細

1.    閲嶆柊缂栬瘧瀹㈡埛绔�锛屼娇涔嬫敮鎸佸瓧绗﹂泦銆傝�峰弬瑙�2.8.2鑺傦紝鈥滃吀鍨嬮厤缃�閫夐」鈥�銆�

2.    涓哄�㈡埛绔�鎸囧畾瀛楃�﹂泦瀹氫箟鏂囦欢鎵�鍦ㄧ殑鐩�褰曘�傚�逛簬寰堝�氬�㈡埛绔�锛屽彲浣跨敤鈥�--character-sets-dir鈥濋�夐」瀹屾垚璇ヤ换鍔°��

3.    灏嗗瓧绗﹂泦瀹氫箟鏂囦欢澶嶅埗鍒板�㈡埛绔�棰勬湡鐨勪綅缃�銆�

濡傛灉閬囧埌鈥�ERROR '...'鏈�鍙戠幇(errno: 23)鈥�锛�鈥�鏃犳硶鎵撳紑鏂囦欢锛�... (errno: 24)鈥�锛屾垨鏉ヨ嚜MySQL鐨勫叿鏈�errno 23鎴�errno 24鐨勫叾瀹冮敊璇�锛屽畠琛ㄧず鏈�涓�MySQL鏈嶅姟鍣ㄥ垎閰嶈冻澶熺殑鏂囦欢鎻忚堪绗�銆備綘鍙�浠ヤ娇鐢�perror瀹炵敤宸ュ叿鏉ヤ簡瑙ｉ敊璇�缂栧彿鐨勫惈涔夛細

shell> perror 23

閿欒��浠ｇ爜23锛氭枃浠惰〃婧㈠嚭

shell> perror 24

閿欒��浠ｇ爜24锛氭墦寮�鏂囦欢杩囧��

shell> perror 11

閿欒��浠ｇ爜11锛氳祫婧愭殏鏃朵笉鍙�鐢�

杩欓噷鐨勯棶棰樻槸锛�mysqld姝ｈ瘯鍥惧悓鏃舵墦寮�杩囧�氱殑鏂囦欢銆備綘鍙�浠ラ�氱煡mysqld涓嶈�佷竴娆℃墦寮�杩囧�氭枃浠讹紝鎴栧�炲姞mysqld鍙�鐢ㄦ枃浠舵弿杩扮�︾殑鏁扮洰銆�

瑕佹兂閫氱煡mysqld灏嗕竴娆℃墦寮�鐨勬枃浠舵帶鍒跺湪杈冨皬鐨勬暟鐩�涓婏紝鍙�闄嶄綆table_cache绯荤粺鍙橀噺鐨勫�硷紙锛夛紝浠庤�屽噺灏戣〃楂橀�熺紦鍐诧紙榛樿�ゅ�间负64锛夈�傞檷浣�max_connections鐨勫�间篃鑳介檷浣�鎵撳紑鏂囦欢鐨勬暟鐩�锛堥粯璁ゅ�间负100锛夈��

瑕佹兂鏇存敼mysqld鍙�鐢ㄧ殑鏂囦欢鎻忚堪绗︾殑鏁扮洰锛屽彲鍦�mysqld_safe涓婁娇鐢ㄢ��--open-files-limit鈥�閫夐」鎴栬�剧疆锛堣嚜MySQL 3.23.30寮�濮嬶級open_files_limit绯荤粺鍙橀噺銆傝�峰弬瑙�5.3.3鑺傦紝鈥滄湇鍔″櫒绯荤粺鍙橀噺鈥�銆傝�剧疆杩欎簺鍊肩殑鏈�绠�鍗曟柟寮忔槸鍦ㄩ�夐」鏂囦欢涓�澧炲姞1涓�閫夐」銆傝�峰弬瑙�4.3.2鑺傦紝鈥滀娇鐢ㄩ�夐」鏂囦欢鈥�銆傚�傛灉mysqld鐨勭増鏈�杈冧綆锛屼笉鏀�鎸佽�剧疆鎵撳紑鏂囦欢鐨勬暟鐩�锛屽彲缂栬緫mysqld_safe鑴氭湰銆傚湪鑴氭湰涓�鏈�1涓�娉ㄩ噴鎺夌殑琛�ulimit -n 256銆備綘鍙�浠ュ垹闄�鈥�#鈥欏瓧绗﹀彇娑堝�硅�ヨ�岀殑娉ㄩ噴锛屾洿鏀规暟鍊�256锛屼互璁剧疆mysqld鍙�鐢ㄧ殑鏂囦欢鎻忚堪绗︽暟鐩�銆�

鈥�--open-files-limit鈥�鍜�ulimit鑳藉�熷�炲姞鏂囦欢鎻忚堪绗︾殑鏁扮洰锛屼絾鏈�楂樹笉鑳借秴杩囨搷浣滅郴缁熼檺鍒剁殑鏁扮洰銆傛�ゅ�栬繕鏈�1涓�鈥滅‖鈥濋檺鍒讹紝浠呭綋浠ユ牴鐢ㄦ埛韬�浠藉惎鍔�mysqld_safe鎴�mysqld鏃舵墠鑳借�嗙洊瀹冿紙璇疯�颁綇锛屽湪璇ユ儏鍐典笅锛岃繕闇�浣跨敤鈥�--user鈥濋�夐」鍚�鍔ㄦ湇鍔″櫒锛屼互渚垮湪鍚�鍔ㄥ悗涓嶅啀浠ユ牴鐢ㄦ埛韬�浠界户缁�杩愯�岋級銆傚�傛灉闇�瑕佸�炲姞鎿嶄綔绯荤粺闄愬埗鐨勫�瑰悇杩涚▼鍙�鐢ㄦ枃浠舵弿杩扮�︾殑鏁扮洰锛岃�峰弬闃呯郴缁熸枃妗ｃ��

娉ㄩ噴锛�濡傛灉杩愯��tcsh shell锛�ulimit涓嶅伐浣滐紒璇锋眰褰撳墠闄愬埗鍊兼椂锛�tcsh杩樿兘閫氭姤涓嶆�ｇ‘鐨勫�笺�傚湪璇ユ儏鍐典笅锛屽簲浣跨敤sh鍚�鍔�mysqld_safe銆�

褰撲綘閾炬帴鍒板簲鐢ㄧ▼搴忎互浣跨敤MySQL瀹㈡埛绔�搴撴椂锛屽彲鑳戒細閬囧埌浠�mysql_寮�濮嬬殑鏈�瀹氫箟寮曠敤閿欒��锛屽�備笅鎵�绀猴細

/tmp/ccFKsdPa.o: 鍦ㄥ嚱鏁�`main'涓�:

/tmp/ccFKsdPa.o(.text+0xb): 瀵�`mysql_init'鐨勬湭瀹氫箟寮曠敤銆�

/tmp/ccFKsdPa.o(.text+0x31): 瀵�`mysql_real_connect'鐨勬湭瀹氫箟寮曠敤銆�

/tmp/ccFKsdPa.o(.text+0x57): 瀵�`mysql_real_connect'鐨勬湭瀹氫箟寮曠敤銆�

/tmp/ccFKsdPa.o(.text+0x69): 瀵�`mysql_error'鐨勬湭瀹氫箟寮曠敤銆�

/tmp/ccFKsdPa.o(.text+0x9a): 瀵�`mysql_close'鐨勬湭瀹氫箟寮曠敤銆�

閫氳繃鍦ㄩ摼鎺ュ懡浠ゅ悗澧炲姞鈥�-Ldir_path -lmysqlclient鈥濋�夐」锛屽簲鑳借В鍐宠�ラ棶棰橈紝鍏朵腑锛�dir_path浠ｈ〃瀹㈡埛绔�搴撴墍鍦ㄧ洰褰曠殑璺�寰勫悕銆傝�佹兂纭�瀹氭�ｇ‘鐨勭洰褰曪紝鍙�灏濊瘯涓嬭堪鍛戒护锛�

shell> mysql_config --libs

鏉ヨ嚜mysql_config鐨勮緭鍑哄彲鑳戒細鎸囨槑搴斿湪閾炬帴鍛戒护涓婃寚瀹氱殑鍏朵粬搴撱��

瀵逛簬闈炲帇缂╂垨鍘嬬缉鍑芥暟锛屽�傛灉閬囧埌鏈�瀹氫箟寮曠敤閿欒��锛屽彲鍦ㄩ摼鎺ュ懡浠ゅ悗娣诲姞-lz锛屽苟鍐嶆�″皾璇曘��

瀵逛簬搴斿湪绯荤粺涓婂瓨鍦ㄧ殑鍑芥暟锛堝��connect锛夛紝濡傛灉閬囧埌鏈�瀹氫箟寮曠敤閿欒��锛岃�锋��鏌ョ浉鍏冲嚱鏁扮殑鎵嬪唽椤碉紝浠ヤ究纭�瀹氬簲鍦ㄩ摼鎺ュ懡浠や笂澧炲姞鍝�浜涘簱銆�

瀵逛簬绯荤粺涓婁笉瀛樺湪鐨勫嚱鏁帮紝鍙�鑳戒細閬囧埌鏈�瀹氫箟寮曠敤閿欒��锛屽�備笅鎵�绀猴細

mf_format.o(.text+0x201): 瀵�`__lxstat'鐨勬湭瀹氫箟寮曠敤銆�

瀹冮�氬父鎰忓懗鐫�浣犵殑MySQL瀹㈡埛绔�搴撴槸鍦ㄤ笌浣犵殑绯荤粺涓�100锛呭吋瀹圭殑绯荤粺涓婄紪璇戠殑銆傚湪璇ユ儏鍐典笅锛屽簲涓嬭浇鏈�鏂扮殑MySQL婧愮爜鍒嗗彂鐗堬紝骞惰嚜宸辩紪璇�MySQL銆傝�峰弬瑙�2.8鑺傦紝鈥滀娇鐢ㄦ簮鐮佸垎鍙戠増瀹夎�匨ySQL鈥�銆�

褰撲綘璇曞浘鎵ц��MySQL绋嬪簭鏃讹紝鍙�鑳戒細閬囧埌杩愯�屾椂鏈�瀹氫箟寮曠敤閿欒��銆傚�傛灉杩欑被閿欒��鎸囨槑浜嗕互mysql_寮�濮嬬殑绗﹀彿锛�鎴栨寚鏄庢湭鍙戠幇mysqlclient搴�锛岃繖鎰忓懗鐫�浣犵殑绯荤粺鏃犳硶鎵惧埌鍏变韩鐨�libmysqlclient.so搴撱��瀵瑰叾鐨勬洿姝ｆ柟寮忔槸锛岄�氱煡绯荤粺鍦ㄥ簱鎵�鍦ㄤ綅缃�鎼滅储鍏变韩搴撱�傝�蜂娇鐢ㄤ笌绯荤粺鐩搁�傚簲鐨勪笅杩版柟娉曪細

路         灏�libmysqlclient.so鎵�鍦ㄧ洰褰曠殑璺�寰勬坊鍔犲埌LD_LIBRARY_PATH鐜�澧冨彉閲忎腑銆�

路         灏�libmysqlclient.so鎵�鍦ㄧ洰褰曠殑璺�寰勬坊鍔犲埌LD_LIBRARY鐜�澧冨彉閲忎腑銆�

路         灏�libmysqlclient.so鎷疯礉鍒板彲琚�绯荤粺鎼滅储鐨勭洰褰曚笅锛屽��/lib锛岀劧鍚庨�氳繃鎵ц��ldconfig鏇存柊鍏变韩搴撲俊鎭�銆�

瑙ｅ喅璇ラ棶棰樼殑鍙︿竴绉嶆柟娉曟槸锛屼互闈欐�佹柟寮忓皢浣犵殑绋嬪簭涓庘��-static鈥濋�夐」閾炬帴鍦ㄤ竴璧凤紝鎴栧湪閾炬帴浠ｇ爜涔嬪墠鍒犻櫎鍔ㄦ��MySQL搴撱�備娇鐢ㄧ��2绉嶆柟娉曚箣鍓嶏紝搴旂‘淇濇病鏈変娇鐢ㄥ姩鎬佸簱鐨勫叾瀹冪▼搴忋��

鍦�Windows骞冲彴涓婏紝鑳藉�熶娇鐢ㄦ櫘閫氱敤鎴疯处鎴蜂互Windows鏈嶅姟鏂瑰紡杩愯�屾湇鍔″櫒銆�

鍦�Unix骞冲彴涓婏紝涓嶆槸浠讳綍鐢ㄦ埛閮借兘鍚�鍔ㄥ苟杩愯��MySQL鏈嶅姟鍣�mysqld鐨�銆備絾鏄�锛屽�勪簬瀹夊叏鏂归潰鐨勫師鍥狅紝搴旈伩鍏嶄互Unix鏍圭敤鎴疯韩浠借繍琛屾湇鍔″櫒銆傝�佹兂鏇存敼mysqld锛屼娇涔嬭兘浠ユ�ｅ父鐨勬棤鐗规潈Unix鐢ㄦ埛user_name韬�浠借繍琛岋紝蹇呴』閲囧彇涓嬭堪姝ラ�わ細

濡傛灉鏈嶅姟鍣ㄦ�ｅ湪杩愯�岋紝鍋滄�㈠畠锛堜娇鐢�mysqladmin shutdown锛夈��

鏇存敼鏁版嵁搴撶洰褰曞拰鏂囦欢锛屽厑璁�user_name璇诲啓鍏朵腑鐨勬枃浠讹紙鍙�鑳介渶瑕佷互Unix鏍圭敤鎴疯韩浠藉畬鎴愯繖绫昏�剧疆锛夛細

shell> chown -R user_name /path/to/mysql/datadir

濡傛灉鏈�杩欐牱鍋氾紝褰撲互user_name韬�浠借繍琛屾椂锛屾湇鍔″櫒鏃犳硶璁块棶鏁版嵁搴撴垨琛ㄣ��

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浠�user_name韬�浠藉惎鍔ㄦ湇鍔″櫒銆傚�傛灉浣犳�ｅ湪浣跨敤MySQL 3.22鎴栨洿楂樼増鏈�锛屽彟涓�绉嶅彲閫夋柟寮忔槸锛屼互Unix鏍圭敤鎴疯韩浠藉惎鍔�mysqld锛屽苟浣跨敤--user=user_name閫夐」銆�mysqld鍚�鍔�锛岀劧鍚庡湪鎺ュ彈浠讳綍杩炴帴鍓嶏紝鍒囨崲鑷�Unix鐢ㄦ埛user_name骞朵互璇ョ敤鎴疯韩浠借繍琛屻��

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[mysqld]

user=user_name

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濡傛灉閬囧埌涓庢枃浠惰�稿彲鏈夊叧鐨勯棶棰橈紝鍙�鑳芥暟鍚�鍔�mysqld鏃�UMASK鐜�澧冨彉閲忚�剧疆寰椾笉姝ｇ‘銆備緥濡傦紝褰撲綘鍒涘缓琛ㄦ椂锛�MySQL鍙�鑳戒細鍙戝嚭涓嬭堪閿欒��娑堟伅锛�

ERROR: 鏃犳硶鎵惧埌鏂囦欢锛�'path/with/filename.frm' (Errcode: 13)

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shell> UMASK=384  # = 600 in octal

shell> export UMASK

shell> mysqld_safe &

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shell> UMASK_DIR=504  # = 770 in octal

shell> export UMASK_DIR

shell> mysqld_safe &

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璇峰弬瑙�闄勫綍F锛�鐜�澧冨彉閲�銆�

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濡傛灉浣犱互鍓嶈�剧疆浜嗘牴鐢ㄦ埛瀵嗙爜锛屼絾鍗村繕璁颁簡璇ュ瘑鐮侊紝鍙�璁剧疆鏂扮殑瀵嗙爜銆備笅杩版�ラ�ゆ槸閽堝��Windows骞冲彴鐨勩�傚湪鏈�鑺傚悗闈㈢殑鍐呭�逛腑锛屼粙缁嶄簡閽堝��Unix骞冲彴鐨勬�ラ�ゃ��

鍦�Windows骞冲彴涓嬶紝璇ユ�ラ�ゆ槸锛�

浠ョ郴缁熺�＄悊鍛樿韩浠界櫥褰曞埌绯荤粺銆�

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寮�濮嬭彍鍗�->鎺у埗闈㈡澘->绠＄悊宸ュ叿->鏈嶅姟

鐒跺悗鍦ㄥ垪琛ㄤ腑鎵惧嚭MySQL鏈嶅姟鍣�锛屽苟鍋滄�㈠畠銆�

濡傛灉鏈嶅姟鍣ㄤ笉鏄�浣滀负鏈嶅姟鑰岃繍琛岀殑锛屽彲鑳介渶瑕佷娇鐢ㄤ换鍔＄�＄悊鍣ㄦ潵寮哄埗鍋滄�㈠畠銆�

鍒涘缓1涓�鏂囨湰鏂囦欢锛屽苟灏嗕笅杩板懡浠ょ疆浜庡崟涓�琛屼腑锛�

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPassword');

鐢ㄤ换鎰忓悕绉颁繚瀛樿�ユ枃浠躲�傚湪鏈�渚嬩腑锛岃�ユ枃浠朵负C:\mysql-init.txt銆�

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寮�濮嬭彍鍗�->杩愯��-> cmd

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鍦�DOS鍛戒护鎻愮ず绗︿笅锛屾墽琛屽懡浠わ細

C:\> C:\mysql\bin\mysqld-nt --init-file=C:\mysql-init.txt

鍦ㄦ湇鍔″櫒鍚�鍔ㄦ椂锛屾墽琛岀敱鈥�--init-file鈥濋�夐」鍛藉悕鐨勬枃浠剁殑鍐呭�癸紝鏇存敼鏍圭敤鎴峰瘑鐮併�傚綋鏈嶅姟鍣ㄦ垚鍔熷惎鍔ㄥ悗锛屽簲鍒犻櫎C:\mysql-init.txt銆�

濡傛灉浣犱娇鐢�MySQL瀹夎�呭悜瀵煎畨瑁呬簡MySQL锛屾垨璁搁渶瑕佹寚瀹氣��--defaults-file鈥�閫夐」锛�

C:\> C:\Program Files\MySQL\MySQL Server 5.1\bin\mysqld-nt.exe

         --defaults-file="C:\Program Files\MySQL\MySQL Server 5.1\my.ini"

         --init-file=C:\mysql-init.txt

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浠�Unix鏍圭敤鎴疯韩浠姐�佹垨浠ヨ繍琛�mysqld鏈嶅姟鍣ㄧ殑鐩稿悓韬�浠界櫥褰曞埌绯荤粺銆�

鎵惧埌鍖呭惈鏈嶅姟鍣ㄨ繘绋�ID鐨�.pid鏂囦欢銆傝�ユ枃浠剁殑鍑嗙‘浣嶇疆鍜屽悕绉板彇鍐充簬浣犵殑鍒嗗彂鐗堛�佷富鏈哄悕鍜岄厤缃�銆傚父瑙佷綅缃�鏄�/var/lib/mysql/銆�/var/run/mysqld/鍜�/usr/local/mysql/data/銆�涓�鑸�鎯呭喌涓嬶紝鏂囦欢鍚嶇殑鎵╁睍鍚嶄负.pid锛屽苟浠�mysqld鎴栫郴缁熺殑涓绘満鍚嶅紑濮嬨��

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shell> kill `cat /mysql-data-directory/host_name.pid`

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鍒涘缓鏂囨湰鏂囦欢锛屽苟灏嗕笅杩板懡浠ゆ斁鍦ㄦ枃浠跺唴鐨�1琛屼笂锛�

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPassword');

鐢ㄤ换鎰忓悕绉颁繚瀛樻枃浠躲�傚�逛簬鏈�渚嬶紝鏂囦欢涓�~/mysql-init銆�

鐢ㄧ壒娈婄殑鈥�--init-file=~/mysql-init鈥濋�夐」閲嶅惎MySQL鏈嶅姟鍣�锛�

shell> mysqld_safe --init-file=~/mysql-init &

鏂囦欢init-file鐨勫唴瀹瑰湪鏈嶅姟鍣ㄥ惎鍔ㄦ椂鎵ц�岋紝鏇存敼鏍圭敤鎴峰瘑鐮併�傛湇鍔″櫒鎴愬姛鍚�鍔ㄥ悗锛屽簲鍒犻櫎~/mysql-init銆�

搴旇兘浣跨敤鏂板瘑鐮佽繘琛岃繛鎺ャ��

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鍋滄��mysqld锛屽苟鐢ㄢ��--skip-grant-tables --user=root鈥�閫夐」閲嶅惎瀹�锛�Windows鐢ㄦ埛鍙�鐪佺暐--user=root閮ㄥ垎锛夈��

浣跨敤涓嬭堪鍛戒护杩炴帴鍒�mysqld鏈嶅姟鍣�锛�

shell> mysql -u root

鍦�mysql瀹㈡埛绔�鍙戝嚭涓嬭堪璇�鍙ワ細

mysql> UPDATE mysql.user SET Password=PASSWORD('newpwd')

    ->                   WHERE User='root';

mysql> FLUSH PRIVILEGES;

鐢ㄦ墦绠椾娇鐢ㄧ殑瀹為檯鏍圭敤鎴峰瘑鐮佹浛鎹⑩��newpwd鈥濄��

搴旇兘浣跨敤鏂板瘑鐮佽繘琛岃繛鎺ャ��

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棣栧厛锛屽簲灏濊瘯鎵惧嚭闂�棰樻槸鍚︿笌mysqld鏈嶅姟鍣ㄦ湁鍏筹紝鎴栨槸鍚︿笌瀹㈡埛绔�鏈夊叧銆傞�氳繃鎵ц��mysqladmin version锛屽彲妫�鏌�mysqld鏈嶅姟鍣ㄨ繍琛屼簡澶氶暱鏃堕棿銆傚�傛灉mysqld瀹曟満骞堕噸鍚�锛屽簲鏌ョ湅鏈嶅姟鍣ㄧ殑閿欒��鏃ュ織浠ユ壘鍑哄師鍥犮�傝�峰弬瑙�5.11.1鑺傦紝鈥滈敊璇�鏃ュ織鈥�銆�

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鍓嶈堪浠嬬粛琛ㄦ槑锛屽湪姝ｅ父鎯呭喌涓嬩笉浼氬嚭鐜版崯鍧忕殑琛�锛岄櫎闈炲嚭鐜颁簡涓嬭堪鎯呭喌涔嬩竴锛�

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(length of what is sorted + sizeof(row pointer))

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mysql> INSERT INTO tbl_name (idate) VALUES ('19970505');

mysql> INSERT INTO tbl_name (idate) VALUES ('97-05-05');

mysql> INSERT INTO tbl_name (idate) VALUES ('1997.05.05');

mysql> INSERT INTO tbl_name (idate) VALUES ('1997 05 05');

mysql> INSERT INTO tbl_name (idate) VALUES ('0000-00-00');

mysql> SELECT idate FROM tbl_name WHERE idate >= '1997-05-05';

mysql> SELECT idate FROM tbl_name WHERE idate >= 19970505;

mysql> SELECT MOD(idate,100) FROM tbl_name WHERE idate >= 19970505;

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mysql> INSERT INTO my_table (phone) VALUES (NULL);

mysql> INSERT INTO my_table (phone) VALUES ('');

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mysql> SELECT * FROM my_table WHERE phone = NULL;

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mysql> SELECT * FROM my_table WHERE phone IS NULL;

mysql> SELECT * FROM my_table WHERE phone = '';

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浣跨敤ORDER BY鏃讹紝棣栧厛灏嗘樉绀�NULL鍊硷紝濡傛灉鎸囧畾浜�DESC鎸夐檷搴忔帓鍒楋紝NULL鍊煎皢鏈�鍚庢樉绀恒��

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mysql> SELECT COUNT(*), COUNT(age) FROM person;

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SELECT SQRT(a*b) AS root FROM tbl_name GROUP BY root HAVING root > 0;

SELECT id, COUNT(*) AS cnt FROM tbl_name GROUP BY id HAVING cnt > 0;

SELECT id AS 'Customer identity' FROM tbl_name;

SELECT id, COUNT(*) AS cnt FROM tbl_name WHERE cnt > 0 GROUP BY id;

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SHOW CREATE TABLE tbl_name;

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shell> mysql test2 < query.sql

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