{"id":78128,"date":"2024-10-16T11:32:16","date_gmt":"2024-10-16T03:32:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/78128\/"},"modified":"2024-10-16T11:32:16","modified_gmt":"2024-10-16T03:32:16","slug":"mysql%e6%8c%87%e4%bb%a4-cursor%ef%bc%88%e6%b8%b8%e6%a8%99%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/78128\/","title":{"rendered":"MySQL\u6307\u4ee4: CURSOR\uff08\u6e38\u6a19\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-cursor%ef%bc%88%e6%b8%b8%e6%a8%99%ef%bc%89-hGlTUPjHbI\">MySQL\u6307\u4ee4: CURSOR\uff08\u6e38\u6a19\uff09<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u806f\u5f0f\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u3002\u7576\u6211\u5011\u9700\u8981\u8655\u7406\u591a\u884c\u8cc7\u6599\u6642\uff0c\u6e38\u6a19\uff08CURSOR\uff09\u662f\u4e00\u500b\u975e\u5e38\u6709\u7528\u7684\u5de5\u5177\u3002\u6e38\u6a19\u5141\u8a31\u958b\u767c\u8005\u9010\u884c\u8655\u7406\u67e5\u8a62\u7d50\u679c\uff0c\u9019\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\u6bd4\u4e00\u6b21\u6027\u8655\u7406\u6574\u500b\u7d50\u679c\u96c6\u66f4\u70ba\u9748\u6d3b\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e6%b8%b8%e6%a8%99%ef%bc%9f-hGlTUPjHbI\">\u4ec0\u9ebc\u662f\u6e38\u6a19\uff1f<\/h2>\n<p>\u6e38\u6a19\u662f\u4e00\u7a2e\u8cc7\u6599\u5eab\u5c0d\u8c61\uff0c\u7528\u65bc\u5728\u67e5\u8a62\u7d50\u679c\u4e2d\u9010\u884c\u6aa2\u7d22\u8cc7\u6599\u3002\u5b83\u63d0\u4f9b\u4e86\u4e00\u7a2e\u65b9\u6cd5\u4f86\u904d\u6b77\u67e5\u8a62\u7d50\u679c\u96c6\uff0c\u4e26\u5c0d\u6bcf\u4e00\u884c\u57f7\u884c\u64cd\u4f5c\u3002\u6e38\u6a19\u7684\u4f7f\u7528\u901a\u5e38\u6d89\u53ca\u4ee5\u4e0b\u5e7e\u500b\u6b65\u9a5f\uff1a<\/p>\n<ul>\n<li>\u5ba3\u544a\u6e38\u6a19<\/li>\n<li>\u6253\u958b\u6e38\u6a19<\/li>\n<li>\u63d0\u53d6\u8cc7\u6599<\/li>\n<li>\u95dc\u9589\u6e38\u6a19<\/li>\n<li>\u91cb\u653e\u6e38\u6a19<\/li>\n<\/ul>\n<h2 id=\"%e6%b8%b8%e6%a8%99%e7%9a%84%e4%bd%bf%e7%94%a8%e7%af%84%e4%be%8b-hGlTUPjHbI\">\u6e38\u6a19\u7684\u4f7f\u7528\u7bc4\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528\u6e38\u6a19\u7684\u57fa\u672c\u7bc4\u4f8b\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>employees<\/code> \u7684\u8868\u683c\uff0c\u4e26\u5e0c\u671b\u9010\u884c\u6aa2\u7d22\u54e1\u5de5\u7684\u59d3\u540d\u548c\u85aa\u6c34\u3002<\/p>\n<pre><code>DELIMITER \/\/\n\nCREATE PROCEDURE GetEmployees()\nBEGIN\n    DECLARE done INT DEFAULT FALSE;\n    DECLARE emp_name VARCHAR(100);\n    DECLARE emp_salary DECIMAL(10,2);\n    \n    -- \u5ba3\u544a\u6e38\u6a19\n    DECLARE emp_cursor CURSOR FOR \n        SELECT name, salary FROM employees;\n    \n    -- \u7576\u6e38\u6a19\u7d50\u675f\u6642\uff0c\u8a2d\u7f6edone\u70baTRUE\n    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;\n\n    -- \u6253\u958b\u6e38\u6a19\n    OPEN emp_cursor;\n\n    -- \u9010\u884c\u63d0\u53d6\u8cc7\u6599\n    read_loop: LOOP\n        FETCH emp_cursor INTO emp_name, emp_salary;\n        IF done THEN\n            LEAVE read_loop;\n        END IF;\n        -- \u5728\u9019\u88e1\u53ef\u4ee5\u5c0d\u6bcf\u4e00\u884c\u8cc7\u6599\u9032\u884c\u64cd\u4f5c\n        SELECT emp_name, emp_salary;\n    END LOOP;\n\n    -- \u95dc\u9589\u6e38\u6a19\n    CLOSE emp_cursor;\nEND \/\/\n\nDELIMITER ;<\/code><\/pre>\n<h2 id=\"%e6%b8%b8%e6%a8%99%e7%9a%84%e5%84%aa%e7%bc%ba%e9%bb%9e-hGlTUPjHbI\">\u6e38\u6a19\u7684\u512a\u7f3a\u9ede<\/h2>\n<h3 id=\"%e5%84%aa%e9%bb%9e-hGlTUPjHbI\">\u512a\u9ede<\/h3>\n<ul>\n<li><strong>\u9010\u884c\u8655\u7406\uff1a<\/strong>\u6e38\u6a19\u5141\u8a31\u958b\u767c\u8005\u9010\u884c\u8655\u7406\u8cc7\u6599\uff0c\u9019\u5728\u9700\u8981\u5c0d\u6bcf\u4e00\u884c\u9032\u884c\u8907\u96dc\u8a08\u7b97\u6216\u64cd\u4f5c\u6642\u975e\u5e38\u6709\u7528\u3002<\/li>\n<li><strong>\u9748\u6d3b\u6027\uff1a<\/strong>\u4f7f\u7528\u6e38\u6a19\u53ef\u4ee5\u5728\u67e5\u8a62\u7d50\u679c\u4e2d\u9032\u884c\u66f4\u9748\u6d3b\u7684\u64cd\u4f5c\uff0c\u4f8b\u5982\u6839\u64da\u67d0\u4e9b\u689d\u4ef6\u904e\u6ffe\u8cc7\u6599\u3002<\/li>\n<\/ul>\n<h3 id=\"%e7%bc%ba%e9%bb%9e-hGlTUPjHbI\">\u7f3a\u9ede<\/h3>\n<ul>\n<li><strong>\u6027\u80fd\u554f\u984c\uff1a<\/strong>\u6e38\u6a19\u7684\u6027\u80fd\u901a\u5e38\u4e0d\u5982\u6279\u91cf\u8655\u7406\uff0c\u56e0\u70ba\u5b83\u5011\u9700\u8981\u9010\u884c\u6aa2\u7d22\u8cc7\u6599\uff0c\u9019\u53ef\u80fd\u5c0e\u81f4\u6548\u7387\u4f4e\u4e0b\u3002<\/li>\n<li><strong>\u8cc7\u6e90\u6d88\u8017\uff1a<\/strong>\u6e38\u6a19\u5728\u4f7f\u7528\u6642\u6703\u4f54\u7528\u7cfb\u7d71\u8cc7\u6e90\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5927\u91cf\u8cc7\u6599\u6642\uff0c\u53ef\u80fd\u6703\u5f71\u97ff\u8cc7\u6599\u5eab\u7684\u6574\u9ad4\u6027\u80fd\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-hGlTUPjHbI\">\u7d50\u8ad6<\/h2>\n<p>\u6e38\u6a19\u5728MySQL\u4e2d\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u9069\u5408\u7528\u65bc\u9700\u8981\u9010\u884c\u8655\u7406\u8cc7\u6599\u7684\u60c5\u6cc1\u3002\u7136\u800c\uff0c\u958b\u767c\u8005\u61c9\u8a72\u8b39\u614e\u4f7f\u7528\uff0c\u56e0\u70ba\u6e38\u6a19\u53ef\u80fd\u6703\u5f71\u97ff\u6027\u80fd\u3002\u5728\u8a31\u591a\u60c5\u6cc1\u4e0b\uff0c\u4f7f\u7528\u6279\u91cf\u64cd\u4f5c\u6216\u5176\u4ed6\u65b9\u6cd5\u53ef\u80fd\u6703\u66f4\u6709\u6548\u7387\u3002\u4e86\u89e3\u6e38\u6a19\u7684\u4f7f\u7528\u65b9\u6cd5\u53ca\u5176\u512a\u7f3a\u9ede\uff0c\u5c07\u6709\u52a9\u65bc\u958b\u767c\u8005\u5728\u8a2d\u8a08\u8cc7\u6599\u5eab\u61c9\u7528\u6642\u505a\u51fa\u66f4\u660e\u667a\u7684\u9078\u64c7\u3002<\/p>\n<p>\u5982\u9700\u9032\u4e00\u6b65\u4e86\u89e3MySQL\u53ca\u5176\u76f8\u95dc\u6280\u8853\uff0c\u60a8\u53ef\u4ee5\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\uff0c\u7372\u53d6\u66f4\u591a\u8cc7\u8a0a\u3002\u7121\u8ad6\u662f <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u9084\u662f\u5176\u4ed6 <a href=\"https:\/\/server.hk\">\u4f3a\u670d\u5668<\/a> \u89e3\u6c7a\u65b9\u6848\uff0c\u6211\u5011\u90fd\u80fd\u63d0\u4f9b\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u4e2d\u7684CURSOR\uff08\u6e38\u6807\uff09\u6307\u4ee4\uff0c\u638c\u63e1\u5982\u4f55\u5728\u6570\u636e\u5e93\u4e2d\u9010\u884c\u5904\u7406\u67e5\u8be2\u7ed3\u679c\uff0c\u63d0\u9ad8\u6570\u636e\u64cd\u4f5c\u6548\u7387\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-78128","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78128","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=78128"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78128\/revisions"}],"predecessor-version":[{"id":78129,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78128\/revisions\/78129"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=78128"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=78128"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=78128"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}