{"id":62,"date":"2023-02-21T08:47:49","date_gmt":"2023-02-21T08:47:49","guid":{"rendered":"https:\/\/blessingcr.com\/?p=62"},"modified":"2023-02-21T08:47:50","modified_gmt":"2023-02-21T08:47:50","slug":"%e9%94%81","status":"publish","type":"post","link":"https:\/\/blessingcr.com\/?p=62","title":{"rendered":"\u9501"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\" id=\"_sUgeenV2\"><\/h3>\n\n\n\n<h1 class=\"wp-block-heading\" id=\"_cVJ5UNhs\">\u8868\u7ea7\u9501\u548c\u884c\u7ea7\u9501<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">MyISAM \u4ec5\u4ec5\u652f\u6301\u8868\u7ea7\u9501(table-level locking)\uff0c\u4e00\u9501\u5c31\u9501\u6574\u5f20\u8868\uff0c\u8fd9\u5728\u5e76\u53d1\u5199\u7684\u60c5\u51b5\u4e0b\u6027\u975e\u5e38\u5dee\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">InnoDB \u4e0d\u5149\u652f\u6301\u8868\u7ea7\u9501(table-level locking)\uff0c\u8fd8\u652f\u6301\u884c\u7ea7\u9501(row-level locking)\uff0c\u9ed8\u8ba4\u4e3a\u884c\u7ea7\u9501\u3002\u884c\u7ea7\u9501\u7684\u7c92\u5ea6\u66f4\u5c0f\uff0c\u4ec5\u5bf9\u76f8\u5173\u7684\u8bb0\u5f55\u4e0a\u9501\u5373\u53ef\uff08\u5bf9\u4e00\u884c\u6216\u8005\u591a\u884c\u8bb0\u5f55\u52a0\u9501\uff09\uff0c\u6240\u4ee5\u5bf9\u4e8e\u5e76\u53d1\u5199\u5165\u64cd\u4f5c\u6765\u8bf4\uff0c InnoDB \u7684\u6027\u80fd\u66f4\u9ad8\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u8868\u7ea7\u9501\u548c\u884c\u7ea7\u9501\u5bf9\u6bd4<\/strong>&nbsp;\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u8868\u7ea7\u9501\uff1a<\/strong>&nbsp;MySQL \u4e2d\u9501\u5b9a\u7c92\u5ea6\u6700\u5927\u7684\u4e00\u79cd\u9501\uff0c\u662f\u9488\u5bf9\u975e\u7d22\u5f15\u5b57\u6bb5\u52a0\u7684\u9501\uff0c\u5bf9\u5f53\u524d\u64cd\u4f5c\u7684\u6574\u5f20\u8868\u52a0\u9501\uff0c\u5b9e\u73b0\u7b80\u5355\uff0c\u8d44\u6e90\u6d88\u8017\u4e5f\u6bd4\u8f83\u5c11\uff0c\u52a0\u9501\u5feb\uff0c\u4e0d\u4f1a\u51fa\u73b0\u6b7b\u9501\u3002\u5176\u9501\u5b9a\u7c92\u5ea6\u6700\u5927\uff0c\u89e6\u53d1\u9501\u51b2\u7a81\u7684\u6982\u7387\u6700\u9ad8\uff0c\u5e76\u53d1\u5ea6\u6700\u4f4e\uff0cMyISAM \u548c InnoDB \u5f15\u64ce\u90fd\u652f\u6301\u8868\u7ea7\u9501\u3002<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u884c\u7ea7\u9501\uff1a<\/strong>&nbsp;MySQL \u4e2d\u9501\u5b9a\u7c92\u5ea6\u6700\u5c0f\u7684\u4e00\u79cd\u9501\uff0c\u662f\u9488\u5bf9\u7d22\u5f15\u5b57\u6bb5\u52a0\u7684\u9501\uff0c\u53ea\u9488\u5bf9\u5f53\u524d\u64cd\u4f5c\u7684\u884c\u8bb0\u5f55\u8fdb\u884c\u52a0\u9501\u3002 \u884c\u7ea7\u9501\u80fd\u5927\u5927\u51cf\u5c11\u6570\u636e\u5e93\u64cd\u4f5c\u7684\u51b2\u7a81\u3002\u5176\u52a0\u9501\u7c92\u5ea6\u6700\u5c0f\uff0c\u5e76\u53d1\u5ea6\u9ad8\uff0c\u4f46\u52a0\u9501\u7684\u5f00\u9500\u4e5f\u6700\u5927\uff0c\u52a0\u9501\u6162\uff0c\u4f1a\u51fa\u73b0\u6b7b\u9501\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"_eLiyVI_K\">\u884c\u7ea7\u9501\u7684\u4f7f\u7528\u6709\u4ec0\u4e48\u6ce8\u610f\u4e8b\u9879\uff1f<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">InnoDB \u7684\u884c\u9501\u662f\u9488\u5bf9\u7d22\u5f15\u5b57\u6bb5\u52a0\u7684\u9501\uff0c\u8868\u7ea7\u9501\u662f\u9488\u5bf9\u975e\u7d22\u5f15\u5b57\u6bb5\u52a0\u7684\u9501\u3002\u5f53\u6211\u4eec\u6267\u884c&nbsp;UPDATE\u3001DELETE&nbsp;\u8bed\u53e5\u65f6\uff0c\u5982\u679c&nbsp;WHERE\u6761\u4ef6\u4e2d\u5b57\u6bb5\u6ca1\u6709\u547d\u4e2d\u552f\u4e00\u7d22\u5f15\u6216\u8005\u7d22\u5f15\u5931\u6548\u7684\u8bdd\uff0c\u5c31\u4f1a\u5bfc\u81f4\u626b\u63cf\u5168\u8868\u5bf9\u8868\u4e2d\u7684\u6240\u6709\u884c\u8bb0\u5f55\u8fdb\u884c\u52a0\u9501\u3002\u8fd9\u4e2a\u5728\u6211\u4eec\u65e5\u5e38\u5de5\u4f5c\u5f00\u53d1\u4e2d\u7ecf\u5e38\u4f1a\u9047\u5230\uff0c\u4e00\u5b9a\u8981\u591a\u591a\u6ce8\u610f\uff01\uff01\uff01<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0d\u8fc7\uff0c\u5f88\u591a\u65f6\u5019\u5373\u4f7f\u7528\u4e86\u7d22\u5f15\u4e5f\u6709\u53ef\u80fd\u4f1a\u8d70\u5168\u8868\u626b\u63cf\uff0c\u8fd9\u662f\u56e0\u4e3a MySQL \u4f18\u5316\u5668\u7684\u539f\u56e0\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"_XFgZhda0\"><\/h3>\n\n\n\n<h1 class=\"wp-block-heading\" id=\"_6BQJi305\">\u5171\u4eab\u9501\u548c\u6392\u4ed6\u9501<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0d\u8bba\u662f\u8868\u7ea7\u9501\u8fd8\u662f\u884c\u7ea7\u9501\uff0c\u90fd\u5b58\u5728\u5171\u4eab\u9501\uff08Share Lock\uff0cS \u9501\uff09\u548c\u6392\u4ed6\u9501\uff08Exclusive Lock\uff0cX \u9501\uff09\u8fd9\u4e24\u7c7b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u5171\u4eab\u9501\uff08S \u9501\uff09<\/strong>&nbsp;\uff1a\u53c8\u79f0\u8bfb\u9501\uff0c\u4e8b\u52a1\u5728\u8bfb\u53d6\u8bb0\u5f55\u7684\u65f6\u5019\u83b7\u53d6\u5171\u4eab\u9501\uff0c\u5141\u8bb8\u591a\u4e2a\u4e8b\u52a1\u540c\u65f6\u83b7\u53d6\uff08\u9501\u517c\u5bb9\uff09\u3002<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u6392\u4ed6\u9501\uff08X \u9501\uff09<\/strong>&nbsp;\uff1a\u53c8\u79f0\u5199\u9501\/\u72ec\u5360\u9501\uff0c\u4e8b\u52a1\u5728\u4fee\u6539\u8bb0\u5f55\u7684\u65f6\u5019\u83b7\u53d6\u6392\u4ed6\u9501\uff0c\u4e0d\u5141\u8bb8\u591a\u4e2a\u4e8b\u52a1\u540c\u65f6\u83b7\u53d6\u3002\u5982\u679c\u4e00\u4e2a\u8bb0\u5f55\u5df2\u7ecf\u88ab\u52a0\u4e86\u6392\u4ed6\u9501\uff0c\u90a3\u5176\u4ed6\u4e8b\u52a1\u4e0d\u80fd\u518d\u5bf9\u8fd9\u6761\u4e8b\u52a1\u52a0\u4efb\u4f55\u7c7b\u578b\u7684\u9501\uff08\u9501\u4e0d\u517c\u5bb9\uff09\u3002<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u6392\u4ed6\u9501\u4e0e\u4efb\u4f55\u7684\u9501\u90fd\u4e0d\u517c\u5bb9\uff0c\u5171\u4eab\u9501\u4ec5\u548c\u5171\u4eab\u9501\u517c\u5bb9\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><\/td><td>S \u9501<\/td><td>X \u9501<\/td><\/tr><tr><td>S \u9501<\/td><td>\u4e0d\u51b2\u7a81<\/td><td>\u51b2\u7a81<\/td><\/tr><tr><td>X \u9501<\/td><td>\u51b2\u7a81<\/td><td>\u51b2\u7a81<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u7531\u4e8e MVCC \u7684\u5b58\u5728\uff0c\u5bf9\u4e8e\u4e00\u822c\u7684&nbsp;SELECT&nbsp;\u8bed\u53e5\uff0cInnoDB \u4e0d\u4f1a\u52a0\u4efb\u4f55\u9501\u3002\u4e0d\u8fc7\uff0c \u4f60\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u8bed\u53e5\u663e\u5f0f\u52a0\u5171\u4eab\u9501\u6216\u6392\u4ed6\u9501\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"># \u5171\u4eab\u9501<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SELECT ... LOCK IN SHARE MODE;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"># \u6392\u4ed6\u9501<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SELECT ... FOR UPDATE;<\/p>\n\n\n\n<h1 class=\"wp-block-heading\" id=\"_lyt4DQIc\">\u610f\u5411\u9501<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u9700\u8981\u7528\u5230\u8868\u9501\u7684\u8bdd\uff0c\u5982\u4f55\u5224\u65ad\u8868\u4e2d\u7684\u8bb0\u5f55\u6ca1\u6709\u884c\u9501\u5462\uff1f\u4e00\u884c\u4e00\u884c\u904d\u5386\u80af\u5b9a\u662f\u4e0d\u884c\uff0c\u6027\u80fd\u592a\u5dee\u3002\u6211\u4eec\u9700\u8981\u7528\u5230\u4e00\u4e2a\u53eb\u505a\u610f\u5411\u9501\u7684\u4e1c\u4e1c\u6765\u5feb\u901f\u5224\u65ad\u662f\u5426\u53ef\u4ee5\u5bf9\u67d0\u4e2a\u8868\u4f7f\u7528\u8868\u9501\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u610f\u5411\u9501\u662f\u8868\u7ea7\u9501\uff0c\u5171\u6709\u4e24\u79cd\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u610f\u5411\u5171\u4eab\u9501\uff08Intention Shared Lock\uff0cIS \u9501\uff09<\/strong>\uff1a\u4e8b\u52a1\u6709\u610f\u5411\u5bf9\u8868\u4e2d\u7684\u67d0\u4e9b\u52a0\u5171\u4eab\u9501\uff08S \u9501\uff09\uff0c\u52a0\u5171\u4eab\u9501\u524d\u5fc5\u987b\u5148\u53d6\u5f97\u8be5\u8868\u7684 IS \u9501\u3002<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u610f\u5411\u6392\u4ed6\u9501\uff08Intention Exclusive Lock\uff0cIX \u9501\uff09<\/strong>\uff1a\u4e8b\u52a1\u6709\u610f\u5411\u5bf9\u8868\u4e2d\u7684\u67d0\u4e9b\u8bb0\u5f55\u52a0\u6392\u4ed6\u9501\uff08X \u9501\uff09\uff0c\u52a0\u6392\u4ed6\u9501\u4e4b\u524d\u5fc5\u987b\u5148\u53d6\u5f97\u8be5\u8868\u7684 IX \u9501\u3002<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u610f\u5411\u9501\u662f\u6709\u6570\u636e\u5f15\u64ce\u81ea\u5df1\u7ef4\u62a4\u7684\uff0c\u7528\u6237\u65e0\u6cd5\u624b\u52a8\u64cd\u4f5c\u610f\u5411\u9501\uff0c\u5728\u4e3a\u6570\u636e\u884c\u52a0\u5171\u4eab \/ \u6392\u4ed6\u9501\u4e4b\u524d\uff0cInooDB \u4f1a\u5148\u83b7\u53d6\u8be5\u6570\u636e\u884c\u6240\u5728\u5728\u6570\u636e\u8868\u7684\u5bf9\u5e94\u610f\u5411\u9501\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u610f\u5411\u9501\u4e4b\u95f4\u662f\u4e92\u76f8\u517c\u5bb9\u7684\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><\/td><td>IS \u9501<\/td><td>IX \u9501<\/td><\/tr><tr><td>IS \u9501<\/td><td>\u517c\u5bb9<\/td><td>\u517c\u5bb9<\/td><\/tr><tr><td>IX \u9501<\/td><td>\u517c\u5bb9<\/td><td>\u517c\u5bb9<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u610f\u5411\u9501\u548c\u5171\u4eab\u9501\u548c\u6392\u5b83\u9501\u4e92\u65a5\uff08\u8fd9\u91cc\u6307\u7684\u662f\u8868\u7ea7\u522b\u7684\u5171\u4eab\u9501\u548c\u6392\u4ed6\u9501\uff0c\u610f\u5411\u9501\u4e0d\u4f1a\u4e0e\u884c\u7ea7\u7684\u5171\u4eab\u9501\u548c\u6392\u4ed6\u9501\u4e92\u65a5\uff09\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><\/td><td>IS \u9501<\/td><td>IX \u9501<\/td><\/tr><tr><td>S \u9501<\/td><td>\u517c\u5bb9<\/td><td>\u4e92\u65a5<\/td><\/tr><tr><td>X \u9501<\/td><td>\u4e92\u65a5<\/td><td>\u4e92\u65a5<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h1 class=\"wp-block-heading\" id=\"_PasIfQTh\"><\/h1>\n","protected":false},"excerpt":{"rendered":"<p>\u8868\u7ea7\u9501\u548c\u884c\u7ea7\u9501 MyISAM \u4ec5\u4ec5\u652f\u6301\u8868\u7ea7\u9501(table-level locking)\uff0c\u4e00\u9501\u5c31\u9501\u6574\u5f20\u8868\uff0c\u8fd9\u5728\u5e76 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[29,32],"class_list":["post-62","post","type-post","status-publish","format-standard","hentry","category-mysql","tag-mysql","tag-32"],"_links":{"self":[{"href":"https:\/\/blessingcr.com\/index.php?rest_route=\/wp\/v2\/posts\/62","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blessingcr.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blessingcr.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blessingcr.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blessingcr.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=62"}],"version-history":[{"count":1,"href":"https:\/\/blessingcr.com\/index.php?rest_route=\/wp\/v2\/posts\/62\/revisions"}],"predecessor-version":[{"id":63,"href":"https:\/\/blessingcr.com\/index.php?rest_route=\/wp\/v2\/posts\/62\/revisions\/63"}],"wp:attachment":[{"href":"https:\/\/blessingcr.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=62"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blessingcr.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=62"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blessingcr.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=62"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}