{"id":94620,"date":"2024-10-19T19:46:15","date_gmt":"2024-10-19T11:46:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/94620\/"},"modified":"2024-10-19T19:46:15","modified_gmt":"2024-10-19T11:46:15","slug":"oracle-%e6%95%b8%e6%93%9a%e5%ba%abscn%e6%a6%82%e5%bf%b5%e6%b7%ba%e6%9e%90","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/94620\/","title":{"rendered":"Oracle \u6578\u64da\u5eabSCN\u6982\u5ff5\u6dfa\u6790"},"content":{"rendered":"<h1 id=\"oracle-%e6%95%b8%e6%93%9a%e5%ba%abscn%e6%a6%82%e5%bf%b5%e6%b7%ba%e6%9e%90-riHchMpZYO\">Oracle \u6578\u64da\u5eabSCN\u6982\u5ff5\u6dfa\u6790<\/h1>\n<p>\u5728Oracle\u6578\u64da\u5eab\u4e2d\uff0c\u7cfb\u7d71\u8b8a\u66f4\u865f\uff08System Change Number\uff0c\u7c21\u7a31SCN\uff09\u662f\u4e00\u500b\u81f3\u95dc\u91cd\u8981\u7684\u6982\u5ff5\u3002SCN\u7528\u65bc\u6a19\u8b58\u6578\u64da\u5eab\u4e2d\u7684\u6bcf\u4e00\u500b\u8b8a\u66f4\uff0c\u7121\u8ad6\u662f\u6578\u64da\u7684\u63d2\u5165\u3001\u66f4\u65b0\u9084\u662f\u522a\u9664\u3002\u9019\u7bc7\u6587\u7ae0\u5c07\u6df1\u5165\u63a2\u8a0eSCN\u7684\u5b9a\u7fa9\u3001\u529f\u80fd\u53ca\u5176\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\u7684\u91cd\u8981\u6027\u3002<\/p>\n<h2 id=\"scn%e7%9a%84%e5%ae%9a%e7%be%a9-riHchMpZYO\">SCN\u7684\u5b9a\u7fa9<\/h2>\n<p>SCN\u662f\u4e00\u500b\u6574\u6578\uff0c\u4ee3\u8868\u6578\u64da\u5eab\u4e2d\u67d0\u4e00\u7279\u5b9a\u6642\u9593\u9ede\u7684\u72c0\u614b\u3002\u6bcf\u7576\u6578\u64da\u5eab\u767c\u751f\u8b8a\u66f4\u6642\uff0cOracle\u6703\u81ea\u52d5\u751f\u6210\u4e00\u500b\u65b0\u7684SCN\uff0c\u9019\u4f7f\u5f97\u6bcf\u500b\u8b8a\u66f4\u90fd\u80fd\u88ab\u552f\u4e00\u6a19\u8b58\u3002SCN\u7684\u589e\u9577\u662f\u55ae\u8abf\u7684\uff0c\u9019\u610f\u5473\u8457\u6bcf\u6b21\u8b8a\u66f4\u5f8c\u7684SCN\u503c\u90fd\u6703\u5927\u65bc\u4e4b\u524d\u7684\u503c\u3002<\/p>\n<h2 id=\"scn%e7%9a%84%e5%8a%9f%e8%83%bd-riHchMpZYO\">SCN\u7684\u529f\u80fd<\/h2>\n<p>SCN\u5728Oracle\u6578\u64da\u5eab\u4e2d\u6709\u591a\u7a2e\u529f\u80fd\uff0c\u4e3b\u8981\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><strong>\u6578\u64da\u4e00\u81f4\u6027\uff1a<\/strong>SCN\u5e6b\u52a9\u78ba\u4fdd\u6578\u64da\u7684\u4e00\u81f4\u6027\uff0c\u7279\u5225\u662f\u5728\u591a\u7528\u6236\u74b0\u5883\u4e2d\u3002\u7576\u4e00\u500b\u7528\u6236\u9032\u884c\u67e5\u8a62\u6642\uff0cOracle\u6703\u4f7f\u7528SCN\u4f86\u78ba\u4fdd\u67e5\u8a62\u7d50\u679c\u53cd\u6620\u7684\u662f\u67d0\u4e00\u7279\u5b9a\u6642\u9593\u9ede\u7684\u6578\u64da\u72c0\u614b\u3002<\/li>\n<li><strong>\u6062\u5fa9\u64cd\u4f5c\uff1a<\/strong>\u5728\u6578\u64da\u5eab\u5d29\u6f70\u6216\u6545\u969c\u7684\u60c5\u6cc1\u4e0b\uff0cSCN\u53ef\u4ee5\u7528\u65bc\u6062\u5fa9\u6578\u64da\u5eab\u5230\u67d0\u4e00\u7279\u5b9a\u7684\u72c0\u614b\u3002\u9019\u5c0d\u65bc\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u53ef\u7528\u6027\u81f3\u95dc\u91cd\u8981\u3002<\/li>\n<li><strong>\u589e\u91cf\u5099\u4efd\uff1a<\/strong>SCN\u5728\u589e\u91cf\u5099\u4efd\u4e2d\u4e5f\u626e\u6f14\u8457\u91cd\u8981\u89d2\u8272\u3002\u901a\u904e\u8a18\u9304SCN\uff0c\u6578\u64da\u5eab\u7ba1\u7406\u54e1\u53ef\u4ee5\u78ba\u5b9a\u54ea\u4e9b\u6578\u64da\u81ea\u4e0a\u6b21\u5099\u4efd\u4ee5\u4f86\u5df2\u7d93\u767c\u751f\u8b8a\u66f4\u3002<\/li>\n<\/ul>\n<h2 id=\"scn%e7%9a%84%e4%bd%bf%e7%94%a8%e7%a4%ba%e4%be%8b-riHchMpZYO\">SCN\u7684\u4f7f\u7528\u793a\u4f8b<\/h2>\n<p>\u5728\u5be6\u969b\u64cd\u4f5c\u4e2d\uff0cSCN\u7684\u4f7f\u7528\u975e\u5e38\u5ee3\u6cdb\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u793a\u4f8b\uff0c\u5c55\u793a\u5982\u4f55\u67e5\u8a62\u7576\u524d\u7684SCN\uff1a<\/p>\n<pre><code>SELECT CURRENT_SCN FROM V$DATABASE;<\/code><\/pre>\n<p>\u9019\u689dSQL\u8a9e\u53e5\u5c07\u8fd4\u56de\u7576\u524d\u6578\u64da\u5eab\u7684SCN\u503c\u3002\u7ba1\u7406\u54e1\u53ef\u4ee5\u6839\u64da\u9019\u500b\u503c\u4f86\u9032\u884c\u6578\u64da\u5eab\u7684\u76e3\u63a7\u548c\u7ba1\u7406\u3002<\/p>\n<h2 id=\"scn%e8%88%87%e5%85%b6%e4%bb%96%e6%a6%82%e5%bf%b5%e7%9a%84%e9%97%9c%e4%bf%82-riHchMpZYO\">SCN\u8207\u5176\u4ed6\u6982\u5ff5\u7684\u95dc\u4fc2<\/h2>\n<p>SCN\u8207\u5176\u4ed6\u6578\u64da\u5eab\u6982\u5ff5\u5bc6\u5207\u76f8\u95dc\uff0c\u4f8b\u5982\uff1a<\/p>\n<ul>\n<li><strong>\u5feb\u7167\uff08Snapshot\uff09\uff1a<\/strong>\u5feb\u7167\u662f\u67d0\u4e00\u7279\u5b9a\u6642\u9593\u9ede\u7684\u6578\u64da\u5eab\u72c0\u614b\uff0cSCN\u5728\u9019\u88e1\u7528\u65bc\u6a19\u8b58\u5feb\u7167\u7684\u751f\u6210\u6642\u9593\u3002<\/li>\n<li><strong>\u4e8b\u52d9\uff08Transaction\uff09\uff1a<\/strong>\u6bcf\u500b\u4e8b\u52d9\u5728\u63d0\u4ea4\u6642\u90fd\u6703\u751f\u6210\u4e00\u500bSCN\uff0c\u9019\u4f7f\u5f97Oracle\u80fd\u5920\u8ffd\u8e64\u4e8b\u52d9\u7684\u72c0\u614b\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-riHchMpZYO\">\u7d50\u8ad6<\/h2>\n<p>SCN\u5728Oracle\u6578\u64da\u5eab\u4e2d\u662f\u4e00\u500b\u4e0d\u53ef\u6216\u7f3a\u7684\u6982\u5ff5\uff0c\u5b83\u4e0d\u50c5\u78ba\u4fdd\u4e86\u6578\u64da\u7684\u4e00\u81f4\u6027\u548c\u5b8c\u6574\u6027\uff0c\u9084\u5728\u6578\u64da\u5eab\u7684\u6062\u5fa9\u548c\u5099\u4efd\u904e\u7a0b\u4e2d\u767c\u63ee\u8457\u91cd\u8981\u4f5c\u7528\u3002\u7406\u89e3SCN\u7684\u904b\u4f5c\u539f\u7406\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u54e1\u4f86\u8aaa\u81f3\u95dc\u91cd\u8981\uff0c\u56e0\u70ba\u9019\u5c07\u5e6b\u52a9\u4ed6\u5011\u66f4\u6709\u6548\u5730\u7ba1\u7406\u548c\u7dad\u8b77\u6578\u64da\u5eab\u7cfb\u7d71\u3002<\/p>\n<p>\u5982\u9700\u4e86\u89e3\u66f4\u591a\u6709\u95dc\u6578\u64da\u5eab\u7ba1\u7406\u548c\u76f8\u95dc\u6280\u8853\u7684\u4fe1\u606f\uff0c\u60a8\u53ef\u4ee5\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\uff0c\u7372\u53d6\u66f4\u591a\u8cc7\u6e90\u548c\u652f\u6301\u3002\u7121\u8ad6\u662f\u9078\u64c7<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u9084\u662f\u5176\u4ed6\u670d\u52d9\uff0c\u6211\u5011\u90fd\u80fd\u63d0\u4f9b\u5c08\u696d\u7684\u89e3\u6c7a\u65b9\u6848\u4ee5\u6eff\u8db3\u60a8\u7684\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6df1\u5165\u63a2\u8a0eOracle\u6578\u64da\u5eab\u4e2d\u7684SCN\u6982\u5ff5\uff0c\u4e86\u89e3\u5176\u5728\u6578\u64da\u4e00\u81f4\u6027\u548c\u6062\u5fa9\u4e2d\u7684\u91cd\u8981\u6027\u53ca\u61c9\u7528\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-94620","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94620","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=94620"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94620\/revisions"}],"predecessor-version":[{"id":94621,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/94620\/revisions\/94621"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=94620"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=94620"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=94620"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}