{"id":178842,"date":"2024-11-08T21:21:19","date_gmt":"2024-11-08T13:21:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/178842\/"},"modified":"2024-11-08T21:21:19","modified_gmt":"2024-11-08T13:21:19","slug":"%e5%a6%82%e4%bd%95%e4%bf%ae%e5%be%a9postgresql%e9%8c%af%e8%aa%a4%e4%bb%a3%e7%a2%bc%ef%bc%9a25008-held_cursor_requires_same_isolation_level%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/178842\/","title":{"rendered":"\u5982\u4f55\u4fee\u5fa9PostgreSQL\u932f\u8aa4\u4ee3\u78bc\uff1a25008 &#8211; held_cursor_requires_same_isolation_level\uff1f"},"content":{"rendered":"<h1 id=\"%e5%a6%82%e4%bd%95%e4%bf%ae%e5%be%a9postgresql%e9%8c%af%e8%aa%a4%e4%bb%a3%e7%a2%bc%ef%bc%9a25008-held_cursor_requires_same_isolation_level-ArHfRwucUk\">\u5982\u4f55\u4fee\u5fa9PostgreSQL\u932f\u8aa4\u4ee3\u78bc\uff1a25008 &#8211; held_cursor_requires_same_isolation_level<\/h1>\n<p>\u5728\u4f7f\u7528PostgreSQL\u6578\u64da\u5eab\u6642\uff0c\u958b\u767c\u8005\u53ef\u80fd\u6703\u9047\u5230\u5404\u7a2e\u932f\u8aa4\u4ee3\u78bc\uff0c\u5176\u4e2d\u4e4b\u4e00\u5c31\u662f\u932f\u8aa4\u4ee3\u78bc25008\u3002\u9019\u500b\u932f\u8aa4\u901a\u5e38\u51fa\u73fe\u5728\u4f7f\u7528\u6e38\u6a19\u6642\uff0c\u7279\u5225\u662f\u7576\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225\u8207\u7576\u524d\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u4e0d\u4e00\u81f4\u6642\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u9019\u500b\u932f\u8aa4\u7684\u539f\u56e0\u53ca\u5176\u89e3\u6c7a\u65b9\u6848\u3002<\/p>\n<h2 id=\"%e9%8c%af%e8%aa%a4%e4%bb%a3%e7%a2%bc25008%e7%9a%84%e5%8e%9f%e5%9b%a0-ArHfRwucUk\">\u932f\u8aa4\u4ee3\u78bc25008\u7684\u539f\u56e0<\/h2>\n<p>PostgreSQL\u7684\u6e38\u6a19\u662f\u4e00\u7a2e\u7528\u65bc\u67e5\u8a62\u7d50\u679c\u96c6\u7684\u6578\u64da\u7d50\u69cb\uff0c\u5141\u8a31\u7528\u6236\u9010\u884c\u8655\u7406\u67e5\u8a62\u7d50\u679c\u3002\u7576\u4f60\u5728\u4e00\u500b\u4e8b\u52d9\u4e2d\u6253\u958b\u6e38\u6a19\u6642\uff0c\u8a72\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225\u5fc5\u9808\u8207\u7576\u524d\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u76f8\u540c\u3002\u5982\u679c\u4e0d\u4e00\u81f4\uff0cPostgreSQL\u5c07\u8fd4\u56de\u932f\u8aa4\u4ee3\u78bc25008\uff0c\u63d0\u793a\u201cheld_cursor_requires_same_isolation_level\u201d\u3002<\/p>\n<p>\u9019\u500b\u932f\u8aa4\u901a\u5e38\u767c\u751f\u5728\u4ee5\u4e0b\u60c5\u6cc1\uff1a<\/p>\n<ul>\n<li>\u5728\u4e00\u500b\u4e8b\u52d9\u4e2d\u4f7f\u7528\u4e86\u4e0d\u540c\u7684\u9694\u96e2\u7d1a\u5225\u4f86\u6253\u958b\u6e38\u6a19\u3002<\/li>\n<li>\u5728\u4e00\u500b\u4e8b\u52d9\u4e2d\u5617\u8a66\u4f7f\u7528\u5df2\u7d93\u5728\u53e6\u4e00\u500b\u4e8b\u52d9\u4e2d\u6253\u958b\u7684\u6e38\u6a19\u3002<\/li>\n<li>\u5728\u4f7f\u7528\u6e38\u6a19\u7684\u904e\u7a0b\u4e2d\uff0c\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u88ab\u66f4\u6539\u3002<\/li>\n<\/ul>\n<h2 id=\"postgresql%e7%9a%84%e9%9a%94%e9%9b%a2%e7%b4%9a%e5%88%a5-ArHfRwucUk\">PostgreSQL\u7684\u9694\u96e2\u7d1a\u5225<\/h2>\n<p>\u5728\u89e3\u6c7a\u9019\u500b\u554f\u984c\u4e4b\u524d\uff0c\u4e86\u89e3PostgreSQL\u7684\u9694\u96e2\u7d1a\u5225\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002PostgreSQL\u652f\u6301\u56db\u7a2e\u9694\u96e2\u7d1a\u5225\uff1a<\/p>\n<ul>\n<li><strong>\u8b80\u672a\u63d0\u4ea4\uff08Read Uncommitted\uff09<\/strong><\/li>\n<li><strong>\u8b80\u5df2\u63d0\u4ea4\uff08Read Committed\uff09<\/strong><\/li>\n<li><strong>\u53ef\u91cd\u8907\u8b80\uff08Repeatable Read\uff09<\/strong><\/li>\n<li><strong>\u4e32\u884c\u5316\uff08Serializable\uff09<\/strong><\/li>\n<\/ul>\n<p>\u6bcf\u7a2e\u9694\u96e2\u7d1a\u5225\u90fd\u6709\u5176\u7279\u5b9a\u7684\u884c\u70ba\u548c\u9069\u7528\u5834\u666f\u3002\u7576\u4f60\u5728\u4e00\u500b\u4e8b\u52d9\u4e2d\u4f7f\u7528\u6e38\u6a19\u6642\uff0c\u5fc5\u9808\u78ba\u4fdd\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225\u8207\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u4e00\u81f4\u3002<\/p>\n<h2 id=\"%e5%a6%82%e4%bd%95%e4%bf%ae%e5%be%a9%e9%8c%af%e8%aa%a4%e4%bb%a3%e7%a2%bc25008-ArHfRwucUk\">\u5982\u4f55\u4fee\u5fa9\u932f\u8aa4\u4ee3\u78bc25008<\/h2>\n<p>\u8981\u4fee\u5fa9\u932f\u8aa4\u4ee3\u78bc25008\uff0c\u53ef\u4ee5\u63a1\u53d6\u4ee5\u4e0b\u5e7e\u500b\u6b65\u9a5f\uff1a<\/p>\n<h3 id=\"1-%e7%a2%ba%e8%aa%8d%e4%ba%8b%e5%8b%99%e7%9a%84%e9%9a%94%e9%9b%a2%e7%b4%9a%e5%88%a5-ArHfRwucUk\">1. \u78ba\u8a8d\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225<\/h3>\n<pre><code>SHOW TRANSACTION ISOLATION;<\/code><\/pre>\n<p>\u4f7f\u7528\u4e0a\u8ff0\u547d\u4ee4\u53ef\u4ee5\u67e5\u770b\u7576\u524d\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u3002\u78ba\u4fdd\u5728\u6253\u958b\u6e38\u6a19\u4e4b\u524d\uff0c\u4e86\u89e3\u7576\u524d\u7684\u9694\u96e2\u7d1a\u5225\u3002<\/p>\n<h3 id=\"2-%e8%a8%ad%e7%bd%ae%e6%b8%b8%e6%a8%99%e7%9a%84%e9%9a%94%e9%9b%a2%e7%b4%9a%e5%88%a5-ArHfRwucUk\">2. \u8a2d\u7f6e\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225<\/h3>\n<p>\u5728\u6253\u958b\u6e38\u6a19\u6642\uff0c\u53ef\u4ee5\u660e\u78ba\u6307\u5b9a\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>BEGIN;\nSET TRANSACTION ISOLATION LEVEL SERIALIZABLE;\nDECLARE my_cursor CURSOR FOR SELECT * FROM my_table;\n<\/code><\/pre>\n<p>\u9019\u6a23\u53ef\u4ee5\u78ba\u4fdd\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225\u8207\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u4e00\u81f4\u3002<\/p>\n<h3 id=\"3-%e9%81%bf%e5%85%8d%e5%9c%a8%e4%b8%8d%e5%90%8c%e4%ba%8b%e5%8b%99%e4%b8%ad%e4%bd%bf%e7%94%a8%e5%90%8c%e4%b8%80%e6%b8%b8%e6%a8%99-ArHfRwucUk\">3. \u907f\u514d\u5728\u4e0d\u540c\u4e8b\u52d9\u4e2d\u4f7f\u7528\u540c\u4e00\u6e38\u6a19<\/h3>\n<p>\u5982\u679c\u9700\u8981\u5728\u4e0d\u540c\u7684\u4e8b\u52d9\u4e2d\u4f7f\u7528\u6e38\u6a19\uff0c\u8acb\u78ba\u4fdd\u6bcf\u6b21\u90fd\u91cd\u65b0\u8072\u660e\u6e38\u6a19\uff0c\u800c\u4e0d\u662f\u91cd\u7528\u5df2\u7d93\u95dc\u9589\u7684\u6e38\u6a19\u3002<\/p>\n<pre><code>BEGIN;\nDECLARE my_cursor CURSOR FOR SELECT * FROM my_table;\nFETCH NEXT FROM my_cursor;\nCOMMIT;\n\nBEGIN;\nDECLARE my_cursor CURSOR FOR SELECT * FROM my_table; -- \u91cd\u65b0\u8072\u660e\u6e38\u6a19\nFETCH NEXT FROM my_cursor;\nCOMMIT;\n<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-ArHfRwucUk\">\u7e3d\u7d50<\/h2>\n<p>PostgreSQL\u932f\u8aa4\u4ee3\u78bc25008\u901a\u5e38\u662f\u7531\u65bc\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225\u8207\u7576\u524d\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u4e0d\u4e00\u81f4\u6240\u5f15\u8d77\u7684\u3002\u901a\u904e\u78ba\u8a8d\u4e8b\u52d9\u7684\u9694\u96e2\u7d1a\u5225\u3001\u8a2d\u7f6e\u6e38\u6a19\u7684\u9694\u96e2\u7d1a\u5225\u4ee5\u53ca\u907f\u514d\u5728\u4e0d\u540c\u4e8b\u52d9\u4e2d\u91cd\u7528\u6e38\u6a19\uff0c\u53ef\u4ee5\u6709\u6548\u5730\u89e3\u6c7a\u9019\u500b\u554f\u984c\u3002\u5c0d\u65bc\u9700\u8981\u7a69\u5b9a\u548c\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u61c9\u7528\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\u81f3\u95dc\u91cd\u8981\u3002\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u53ef\u9760\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u670d\u52d9\uff0cServer.HK\u63d0\u4f9b\u591a\u7a2e\u9078\u64c7\u4ee5\u6eff\u8db3\u60a8\u7684\u9700\u6c42\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u4fee\u5fa9PostgreSQL\u932f\u8aa4\u4ee3\u78bc25008\uff0c\u89e3\u6c7aheld_cursor_requires_same_isolation_level\u554f\u984c\uff0c\u78ba\u4fdd\u6e38\u6a19\u9694\u96e2\u7d1a\u5225\u4e00\u81f4\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-178842","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/178842","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=178842"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/178842\/revisions"}],"predecessor-version":[{"id":178843,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/178842\/revisions\/178843"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=178842"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=178842"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=178842"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}