InnoDB 鏄?MySQL 鏁版嵁搴撲腑涓€绉嶅瓨鍌ㄥ紩鎿庯紝瀹冧娇鐢ㄤ簡澶氱増鏈苟鍙戞帶鍒讹紙MVCC锛夋潵瑙ｅ喅骞昏锛圥hantom Read锛夐棶棰樸€傚够璇绘槸鎸囧湪鍚屼竴浜嬪姟涓紝鐢变簬鍏朵粬浜嬪姟鎻掑叆鎴栧垹闄や簡绗﹀悎鏌ヨ鏉′欢鐨勮锛屽鑷磋浜嬪姟鍦ㄦ墽琛岀浉鍚屾煡璇㈡椂锛岃繑鍥炵殑缁撴灉闆嗗彂鐢熶簡鍙樺寲銆?/p>

涓嬮潰鏄?InnoDB 濡備綍瑙ｅ喅骞昏闂鐨勫嚑绉嶆満鍒讹細

1. 浜嬪姟闅旂绾у埆锛欼nnoDB 鎻愪緵浜嗗涓簨鍔￠殧绂荤骇鍒紝鍖呮嫭璇绘湭鎻愪氦锛圧ead Uncommitted锛夈€佽宸叉彁浜わ紙Read Committed锛夈€佸彲閲嶅璇伙紙Repeatable Read锛夊拰涓茶鍖栵紙Serializable锛夈€傚湪鍙噸澶嶈鍜屼覆琛屽寲闅旂绾у埆涓嬶紝InnoDB 浣跨敤閿佹垨 MVCC 鏈哄埗鏉ヨВ鍐冲够璇婚棶棰樸€?/p>

2. MVCC锛堝鐗堟湰骞跺彂鎺у埗锛夛細InnoDB 浣跨敤浜嗗啓鍏ユ椂澶嶅埗锛坈opy-on-write锛夋妧鏈潵瀹炵幇 MVCC銆傚湪璇诲彇鏁版嵁鏃讹紝姣忎釜浜嬪姟浼氱湅鍒颁竴涓暟鎹揩鐓э紝鑰屼笉鏄疄闄呯殑鏁版嵁銆傚綋涓€涓簨鍔″紑濮嬫椂锛孖nnoDB 浼氬皢褰撳墠鐨勬暟鎹簱鐘舵€侊紙鍗冲凡鎻愪氦鐨勬暟鎹級鍒涘缓涓€涓揩鐓э紝骞跺湪璇ヤ簨鍔＄粨鏉熷墠閮戒娇鐢ㄨ繖涓揩鐓с€傝繖鏍凤紝鍗充娇鍏朵粬浜嬪姟鍦ㄦ鏈熼棿鎻掑叆鎴栧垹闄や簡绗﹀悎鏌ヨ鏉′欢鐨勮锛屽綋鍓嶄簨鍔′粛鐒跺彲浠ョ湅鍒颁竴鑷寸殑缁撴灉锛岄伩鍏嶄簡骞昏闂銆?/p>

3. Next-Key Locks锛欼nnoDB 杩樹娇鐢ㄤ簡 Next-Key Locks 鏉ラ槻姝㈠够璇汇€侼ext-Key Locks 鏄竴绉嶇粍鍚堜簡绱㈠紩閿€煎拰闂撮殭閿佺殑閿佹満鍒躲€傚綋涓€涓簨鍔℃墽琛岃寖鍥存煡璇㈡椂锛孖nnoDB 浼氬鏌ヨ鎵€娑夊強鐨勭储寮曢敭鍊煎拰闂撮殭杩涜鍔犻攣锛屼繚璇佸叾浠栦簨鍔℃棤娉曟彃鍏ユ垨鍒犻櫎绗﹀悎鏌ヨ鏉′欢鐨勮锛屼粠鑰岄伩鍏嶄簡骞昏闂銆?/p>

鎬讳箣锛孖nnoDB 浣跨敤浜嗕簨鍔￠殧绂荤骇鍒€丮VCC 鍜?Next-Key Locks 绛夋満鍒舵潵瑙ｅ喅骞昏闂锛屼繚璇佷簡鏁版嵁鐨勪竴鑷存€у拰鍙潬鎬с€?/p>