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甯哥敤sql:
SHOW VARIABLES LIKE 'character%';鏌ョ湅瀛楃闆?br />
SHOW VARIABLES LIKE 'collation_%';
show engines;鏌ョ湅寮曟搸
show databases; 鏌ョ湅鏁版嵁搴?/p>
show tables;
desc table_name;
GRANT ALL PRIVILEGES ON *.* TO 'guming'@'localhost' IDENTIFIED BY 'guming' WITH GRANT OPTION;鎺堟潈
show PRIVILEGES;鏌ョ湅鏉冮檺
show grants for test@localhost;鏌ョ湅鐢ㄦ埛鏉冮檺
select * from mysql.user where user='test';
鍑芥暟
閫昏緫:case when,isnull,IFnull絳?/p>
鏁板:mod,cell,floor,round(),trancate(),abs()
瀛楃涓插嚱鏁幫細rtrim,ltrim,substring,locate(),INSTR(),length,left,right
REPEAT(str,count)
榪斿洖涓涓敱閲嶅鐨勫瓧絎︿覆str 緇勬垚鐨勫瓧絎︿覆錛屽瓧絎︿覆str鐨勬暟鐩瓑浜巆ount 銆?鑻?count <= 0,鍒欒繑鍥炰竴涓┖瀛楃涓層傝嫢str 鎴?count 涓?NULL錛屽垯榪斿洖 NULL 銆?br />
REPLACE(str,from_str,to_str)
榪斿洖瀛楃涓瞫tr 浠ュ強鎵鏈夎瀛楃涓瞭o_str鏇夸唬鐨勫瓧絎︿覆from_str 銆?br />
REVERSE(str)
榪斿洖瀛楃涓?str 錛岄『搴忓拰瀛楃欏哄簭鐩稿弽銆?br />
鏃ユ湡鍑芥暟錛歝urrent_date,datediff,adddate,date_add,dayofweek,dayofyear,dayofmonth,month,hour(),
str_to_date: SELECT STR_TO_DATE('20031031',GET_FORMAT(DATE,'ISO'));
select date_format(current_date(),'%Y-%m-%d %W');
select extract(YEAR_MONTH FROM current_date());
杞崲鍑芥暟錛?br />
cast:鍙嬌鐢–AST()鍑芥暟灝嗘煇涓艱漿涓哄彟澶栦竴縐嶇被鍨嬨侰ONVERT
convert_TZ:CONVERT_TZ() 灝嗘椂闂存棩鏈熷糳t 浠巉rom_tz 緇欏嚭鐨勬椂鍖鴻漿鍒皌o_tz緇欏嚭鐨勬椂鍖?br />
concat:榪斿洖緇撴灉涓鴻繛鎺ュ弬鏁頒駭鐢熺殑瀛楃涓層傚鏈変換浣曚竴涓弬鏁頒負NULL 錛屽垯榪斿洖鍊間負 NULL銆?br />
鍏ㄦ枃媯绱?br />
SELECT * FROM articles WHERE MATCH (title,body) AGAINST ('database');
鍦ㄩ粯璁ょ姸鎬佷笅, 鎼滅儲鐨勬墽琛屾柟寮忎負涓嶅尯鍒嗗ぇ灝忓啓鏂瑰紡銆傜劧鑰?浣犲彲浠ラ氳繃瀵圭紪鍏ョ儲寮曠殑鍒椾嬌鐢ㄤ簩榪涘埗鎺掑簭鏂瑰紡鎵ц鍖哄垎澶у皬鍐欑殑鍏ㄦ枃鎼滅儲銆? 渚嬪錛屽彲浠ュ悜涓涓嬌鐢╨atin1瀛楃闆嗙殑鍒楃粰瀹歭atin1_bin 鐨勬帓搴忔柟寮忥紝瀵逛簬鍏ㄦ枃鎼滅儲鍖哄垎澶у皬鍐欍?br />
鍒╃敤IN BOOLEAN MODE淇敼紼嬪簭錛?MySQL 涔熷彲浠ユ墽琛屽竷?yōu)當鍏ㄦ枃鎼滅储锛?br />
mysql> SELECT * FROM articles WHERE MATCH (title,body)
-> AGAINST ('+MySQL -YourSQL' IN BOOLEAN MODE);
榪欎釜闂媯绱㈡墍鏈夊寘鍚崟璇?#8220;MySQL”鐨勮錛屼絾涓嶆绱㈠寘鍚崟璇?#8220;YourSQL”鐨勮銆?br />
鍏ㄦ枃鎼滅儲鏀寔鏌ヨ鎵╁睍鍔熻兘 (鐗瑰埆鏄叾澶氬彉鐨?#8220;鐩叉煡璇㈡墿灞曞姛鑳?#8221; )銆傝嫢鎼滅儲鐭鐨勯暱搴﹁繃鐭? 閭ｄ箞鐢ㄦ埛鍒欓渶瑕佷緷闈犲叏鏂囨悳绱㈠紩鎿庨氬父緙轟箯鐨勫唴闅愮煡璇嗚繘琛屾煡璇€傝繖鏃訛紝鏌ヨ鎵╁睍鍔熻兘閫氬父寰堟湁鐢ㄣ備緥濡? 鏌愪綅鎼滅儲 “database” 涓璇嶇殑鐢ㄦ埛錛?br />
鍙兘璁や負“MySQL”銆?#8220;Oracle”銆?#8220;DB2” and “RDBMS”鍧囦負絎﹀悎 “databases”鐨勯」錛屽洜姝ら兘搴旇榪斿洖銆傝繖鏃負鍐呴殣鐭ヨ瘑銆?
mysql> SELECT * FROM articles
-> WHERE MATCH (title,body)
-> AGAINST ('database' WITH QUERY EXPANSION);
鍔犲瘑鍑芥暟錛?br />
ENCRYPT()
md5()
password()
瀛楃闆嗘搷浣?br />
SELECT CHARSET(CONVERT('abc' USING utf8));SELECT CHARSET(USER());
鏌ヨ緙撳瓨璁劇疆錛?/strong>
鏈嶅姟鍣ㄥ惎鍔ㄦ椂瑕佺鐢ㄦ煡璇㈢紦瀛橈紝璁劇疆query_cache_size緋葷粺鍙橀噺涓?錛宷uery_cache_type=on
SET GLOBAL query_cache_size = 40000;
SHOW VARIABLES LIKE 'query_cache_size';
SHOW VARIABLES LIKE 'query_cache%';
寮鍚紦瀛樺悗錛?br />
select * from ad_position where id=201;
SHOW STATUS LIKE 'Qcache_hits'; 鏌ヨ鍛戒腑嬈℃暟
SET SESSION query_cache_type = ON;(ON:1,OFF:0,2:DEMAND)
on 鍚敤緙撳瓨錛孲ELECT SQL_NO_CACHE闄ゅ
off 涓嶇敤緙撳瓨錛?br />
DEMAND 浠呭浠ELECT SQL_CACHE寮濮嬬殑閭ｄ簺鏌ヨ璇彞鍚敤緙撳瓨銆?br />
娓呴櫎緙撳瓨錛?/strong>
鍙互浣跨敤FLUSH QUERY CACHE璇彞鏉ユ竻鐞嗘煡璇㈢紦瀛樼鐗囦互鎻愰珮鍐呭瓨浣跨敤鎬ц兘銆傝璇彞涓嶄粠緙撳瓨涓Щ鍑轟換浣曟煡璇€?br />
RESET QUERY CACHE璇彞浠庢煡璇㈢紦瀛樹腑縐誨嚭鎵鏈夋煡璇€侳LUSH TABLES璇彞涔熸墽琛屽悓鏍風殑宸ヤ綔銆?br />
浠涔堢被鍨嬬殑鏁版嵁緙撳瓨錛?/strong>
鏌ヨ緇撴灉闆嗙紦瀛橈紝瀵逛簬鍔ㄦ佺殑緇撴灉闆嗘槸涓嶇紦瀛樼殑銆傚繀欏繪槸涓鏍風殑sql,騫朵笖緇撴灉闆嗘棤鍙樺寲銆?br />
琛ㄦ洿鏂板悗錛屽搴旇〃鐨勭紦瀛樺け鏁堬紝姝ゆ椂鍚屼竴sql鏈夊緢鑳界粨鏋滈泦涓嶅悓浜嗐?br />
娉ㄩ噴錛氭煡璇㈢紦瀛樹笉榪斿洖鏃х殑鏁版嵁銆傚綋琛ㄦ洿鏀瑰悗錛屾煡璇㈢紦瀛樺肩殑鐩稿叧鏉＄洰琚竻絀恒?br />
娉ㄩ噴錛氬鏋滀綘鏈夎澶歮ysqld鏈嶅姟鍣ㄦ洿鏂扮浉鍚岀殑MyISAM琛紝鍦ㄨ繖縐嶆儏鍐典笅鏌ヨ緙撳瓨涓嶈搗浣滅敤銆?br />
娉ㄩ噴錛氭煡璇㈢紦瀛樹笉閫傜敤浜庢湇鍔″櫒鏂圭紪鍐欑殑璇彞銆傚鏋滄鍦ㄤ嬌鐢ㄦ湇鍔″櫒鏂圭紪鍐欑殑璇彞錛岃鑰冭檻鍒拌繖浜涜鍙ュ皢涓嶄細搴旂敤鏌ヨ緙撳瓨
璋冩暣緙撳瓨錛?/strong>
· query_cache_min_res_unit榛樿鍊兼槸4KB銆傝繖搴旇閫傚悎澶ч儴鍒嗘儏鍐點?br />
· 濡傛灉浣犳湁澶ч噺榪斿洖灝忕粨鏋滄暟鎹殑鏌ヨ錛岄粯璁ゆ暟鎹潡澶у皬鍙兘浼氬鑷村唴瀛樼鐗囷紝鏄劇ず涓哄ぇ閲忕┖闂插唴瀛樺潡銆傜敱浜庣己灝戝唴瀛橈紝鍐呭瓨紕庣墖浼氬己鍒舵煡璇㈢紦瀛樹粠緙撳瓨鍐呭瓨涓慨鏁達紙鍒犻櫎錛夋煡璇€傝繖鏃訛紝浣犲簲璇ュ噺灝憅uery_cache_min_res_unit鍙橀噺鐨勫箋?br />
絀洪棽鍧楀拰鐢變簬淇暣鑰岀Щ鍑虹殑鏌ヨ鐨勬暟閲忛氳繃Qcache_free_blocks鍜孮cache_lowmem_prunes鍙橀噺鐨勫肩粰鍑恒?br />
·
濡傛灉澶ч噺鏌ヨ榪斿洖澶х粨鏋滐紙媯鏌?
Qcache_total_blocks鍜孮cache_queries_in_cache鐘舵佸彉閲忥級錛屼綘鍙互閫氳繃澧炲姞
query_cache_min_res_unit鍙橀噺鐨勫兼潵鎻愰珮鎬ц兘銆備絾鏄紝娉ㄦ剰涓嶈浣垮畠鍙樺緱澶ぇ錛堝弬瑙佸墠闈㈢殑鏉＄洰錛夈?br />
鏇存敼瀛樺偍寮曟搸
ALTER TABLE engineTest ENGINE = ARCHIVE;
瀛楃闆嗚緗?
鍦╥ni鏂囦歡涓姞鍏ヤ笅闈㈤厤緗?
default-character-set = utf8
character_set_server = utf8
瀵煎叆鏁版嵁搴撳浠芥椂閬囧埌鐨勯棶棰橈紝絀洪棿涓嶅
淇敼ini鏂囦歡涓殑閰嶇疆錛歮ax_allowed_packet = 16M
鍙傝冩枃妗ｏ細http://doc.mysql.cn/mysql5/refman-5.1-zh.html-chapter/
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