{"id":95454,"date":"2024-10-20T01:11:17","date_gmt":"2024-10-19T17:11:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/95454\/"},"modified":"2024-10-20T01:11:18","modified_gmt":"2024-10-19T17:11:18","slug":"oracle%e6%95%b8%e6%93%9a%e5%ba%ab%ef%bc%9a%e5%b7%a6%e9%80%a3%e6%8e%a5vs%e5%8f%b3%e9%80%a3%e6%8e%a5%ef%bc%8c%e4%bd%a0%e7%9f%a5%e9%81%93%e5%ae%83%e5%80%91%e7%9a%84%e5%8d%80%e5%88%a5%e5%97%8e%ef%bc%9f-o","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/95454\/","title":{"rendered":"Oracle\u6578\u64da\u5eab\uff1a\u5de6\u9023\u63a5VS\u53f3\u9023\u63a5\uff0c\u4f60\u77e5\u9053\u5b83\u5011\u7684\u5340\u5225\u55ce\uff1f (oracle\u6578\u64da\u5eab\u5de6\u9023\u63a5\u53f3\u9023\u63a5)"},"content":{"rendered":"<h1 id=\"oracle%e6%95%b8%e6%93%9a%e5%ba%ab%ef%bc%9a%e5%b7%a6%e9%80%a3%e6%8e%a5vs%e5%8f%b3%e9%80%a3%e6%8e%a5%ef%bc%8c%e4%bd%a0%e7%9f%a5%e9%81%93%e5%ae%83%e5%80%91%e7%9a%84%e5%8d%80%e5%88%a5%e5%97%8e%ef%bc%9f-rXTdrnDLbc\">Oracle\u6578\u64da\u5eab\uff1a\u5de6\u9023\u63a5VS\u53f3\u9023\u63a5\uff0c\u4f60\u77e5\u9053\u5b83\u5011\u7684\u5340\u5225\u55ce\uff1f<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0c\u5c24\u5176\u662fOracle\u6578\u64da\u5eab\uff0c\u9023\u63a5\u64cd\u4f5c\u662f\u67e5\u8a62\u6578\u64da\u7684\u91cd\u8981\u624b\u6bb5\u3002\u5de6\u9023\u63a5\uff08LEFT JOIN\uff09\u548c\u53f3\u9023\u63a5\uff08RIGHT JOIN\uff09\u662f\u5169\u7a2e\u5e38\u898b\u7684\u9023\u63a5\u65b9\u5f0f\uff0c\u5b83\u5011\u5728\u6578\u64da\u67e5\u8a62\u4e2d\u626e\u6f14\u8457\u4e0d\u540c\u7684\u89d2\u8272\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u9019\u5169\u7a2e\u9023\u63a5\u7684\u5b9a\u7fa9\u3001\u7528\u6cd5\u53ca\u5176\u5340\u5225\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u597d\u5730\u7406\u89e3\u9019\u4e9b\u6982\u5ff5\u3002<\/p>\n<h2 id=\"%e5%b7%a6%e9%80%a3%e6%8e%a5%ef%bc%88left-join%ef%bc%89-rXTdrnDLbc\">\u5de6\u9023\u63a5\uff08LEFT JOIN\uff09<\/h2>\n<p>\u5de6\u9023\u63a5\u662f\u4e00\u7a2e\u5c07\u5de6\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u8207\u53f3\u8868\u4e2d\u7b26\u5408\u689d\u4ef6\u7684\u8a18\u9304\u9032\u884c\u9023\u63a5\u7684\u64cd\u4f5c\u3002\u5373\u4f7f\u53f3\u8868\u4e2d\u6c92\u6709\u7b26\u5408\u689d\u4ef6\u7684\u8a18\u9304\uff0c\u5de6\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u4ecd\u7136\u6703\u88ab\u8fd4\u56de\uff0c\u4e26\u4e14\u53f3\u8868\u4e2d\u5c0d\u61c9\u7684\u6b04\u4f4d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h3 id=\"%e8%aa%9e%e6%b3%95%e7%a4%ba%e4%be%8b-rXTdrnDLbc\">\u8a9e\u6cd5\u793a\u4f8b<\/h3>\n<pre><code>SELECT A.*, B.*\nFROM \u8868A A\nLEFT JOIN \u8868B B ON A.\u9375 = B.\u9375;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u67e5\u8a62\u5c07\u8fd4\u56de\u8868A\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff0c\u4e26\u4e14\u53ea\u6709\u5728\u8868B\u4e2d\u6709\u5339\u914d\u7684\u8a18\u9304\u6642\uff0c\u624d\u6703\u986f\u793a\u8868B\u4e2d\u7684\u6578\u64da\u3002\u5982\u679c\u8868B\u4e2d\u6c92\u6709\u5339\u914d\u7684\u8a18\u9304\uff0c\u5247\u8868B\u7684\u6b04\u4f4d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"%e5%8f%b3%e9%80%a3%e6%8e%a5%ef%bc%88right-join%ef%bc%89-rXTdrnDLbc\">\u53f3\u9023\u63a5\uff08RIGHT JOIN\uff09<\/h2>\n<p>\u53f3\u9023\u63a5\u5247\u662f\u5c07\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u8207\u5de6\u8868\u4e2d\u7b26\u5408\u689d\u4ef6\u7684\u8a18\u9304\u9032\u884c\u9023\u63a5\u3002\u5373\u4f7f\u5de6\u8868\u4e2d\u6c92\u6709\u7b26\u5408\u689d\u4ef6\u7684\u8a18\u9304\uff0c\u53f3\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\u4ecd\u7136\u6703\u88ab\u8fd4\u56de\uff0c\u4e26\u4e14\u5de6\u8868\u4e2d\u5c0d\u61c9\u7684\u6b04\u4f4d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h3 id=\"%e8%aa%9e%e6%b3%95%e7%a4%ba%e4%be%8b-rXTdrnDLbc\">\u8a9e\u6cd5\u793a\u4f8b<\/h3>\n<pre><code>SELECT A.*, B.*\nFROM \u8868A A\nRIGHT JOIN \u8868B B ON A.\u9375 = B.\u9375;<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u67e5\u8a62\u5c07\u8fd4\u56de\u8868B\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff0c\u4e26\u4e14\u53ea\u6709\u5728\u8868A\u4e2d\u6709\u5339\u914d\u7684\u8a18\u9304\u6642\uff0c\u624d\u6703\u986f\u793a\u8868A\u4e2d\u7684\u6578\u64da\u3002\u5982\u679c\u8868A\u4e2d\u6c92\u6709\u5339\u914d\u7684\u8a18\u9304\uff0c\u5247\u8868A\u7684\u6b04\u4f4d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"%e5%b7%a6%e9%80%a3%e6%8e%a5%e8%88%87%e5%8f%b3%e9%80%a3%e6%8e%a5%e7%9a%84%e5%8d%80%e5%88%a5-rXTdrnDLbc\">\u5de6\u9023\u63a5\u8207\u53f3\u9023\u63a5\u7684\u5340\u5225<\/h2>\n<ul>\n<li><strong>\u8fd4\u56de\u7684\u8a18\u9304\uff1a<\/strong>\u5de6\u9023\u63a5\u8fd4\u56de\u5de6\u8868\u7684\u6240\u6709\u8a18\u9304\uff0c\u800c\u53f3\u9023\u63a5\u8fd4\u56de\u53f3\u8868\u7684\u6240\u6709\u8a18\u9304\u3002<\/li>\n<li><strong>NULL\u503c\u7684\u8655\u7406\uff1a<\/strong>\u5728\u5de6\u9023\u63a5\u4e2d\uff0c\u53f3\u8868\u7684\u6b04\u4f4d\u53ef\u80fd\u6703\u986f\u793a\u70baNULL\uff1b\u800c\u5728\u53f3\u9023\u63a5\u4e2d\uff0c\u5de6\u8868\u7684\u6b04\u4f4d\u53ef\u80fd\u6703\u986f\u793a\u70baNULL\u3002<\/li>\n<li><strong>\u4f7f\u7528\u5834\u666f\uff1a<\/strong>\u5de6\u9023\u63a5\u901a\u5e38\u7528\u65bc\u9700\u8981\u4fdd\u7559\u5de6\u8868\u6240\u6709\u6578\u64da\u7684\u60c5\u6cc1\uff0c\u800c\u53f3\u9023\u63a5\u5247\u7528\u65bc\u9700\u8981\u4fdd\u7559\u53f3\u8868\u6240\u6709\u6578\u64da\u7684\u60c5\u6cc1\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%af%a6%e9%9a%9b%e6%87%89%e7%94%a8%e6%a1%88%e4%be%8b-rXTdrnDLbc\">\u5be6\u969b\u61c9\u7528\u6848\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6709\u5169\u500b\u8868\uff1a\u9867\u5ba2\u8868\uff08Customers\uff09\u548c\u8a02\u55ae\u8868\uff08Orders\uff09\u3002\u9867\u5ba2\u8868\u5305\u542b\u6240\u6709\u9867\u5ba2\u7684\u8cc7\u6599\uff0c\u800c\u8a02\u55ae\u8868\u50c5\u5305\u542b\u5df2\u4e0b\u8a02\u55ae\u7684\u9867\u5ba2\u8cc7\u6599\u3002<\/p>\n<h3 id=\"%e4%bd%bf%e7%94%a8%e5%b7%a6%e9%80%a3%e6%8e%a5%e6%9f%a5%e8%a9%a2%e6%89%80%e6%9c%89%e9%a1%a7%e5%ae%a2%e5%8f%8a%e5%85%b6%e8%a8%82%e5%96%ae-rXTdrnDLbc\">\u4f7f\u7528\u5de6\u9023\u63a5\u67e5\u8a62\u6240\u6709\u9867\u5ba2\u53ca\u5176\u8a02\u55ae<\/h3>\n<pre><code>SELECT C.\u9867\u5ba2ID, C.\u9867\u5ba2\u59d3\u540d, O.\u8a02\u55aeID\nFROM Customers C\nLEFT JOIN Orders O ON C.\u9867\u5ba2ID = O.\u9867\u5ba2ID;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u9867\u5ba2\u7684\u8cc7\u6599\uff0c\u5373\u4f7f\u67d0\u4e9b\u9867\u5ba2\u6c92\u6709\u4e0b\u8a02\u55ae\uff0c\u5c0d\u61c9\u7684\u8a02\u55aeID\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h3 id=\"%e4%bd%bf%e7%94%a8%e5%8f%b3%e9%80%a3%e6%8e%a5%e6%9f%a5%e8%a9%a2%e6%89%80%e6%9c%89%e8%a8%82%e5%96%ae%e5%8f%8a%e5%85%b6%e9%a1%a7%e5%ae%a2-rXTdrnDLbc\">\u4f7f\u7528\u53f3\u9023\u63a5\u67e5\u8a62\u6240\u6709\u8a02\u55ae\u53ca\u5176\u9867\u5ba2<\/h3>\n<pre><code>SELECT C.\u9867\u5ba2ID, C.\u9867\u5ba2\u59d3\u540d, O.\u8a02\u55aeID\nFROM Customers C\nRIGHT JOIN Orders O ON C.\u9867\u5ba2ID = O.\u9867\u5ba2ID;<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u8a02\u55ae\u7684\u8cc7\u6599\uff0c\u5373\u4f7f\u67d0\u4e9b\u8a02\u55ae\u7684\u9867\u5ba2\u8cc7\u6599\u4e0d\u5b58\u5728\uff0c\u5c0d\u61c9\u7684\u9867\u5ba2\u6b04\u4f4d\u5c07\u986f\u793a\u70baNULL\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-rXTdrnDLbc\">\u7e3d\u7d50<\/h2>\n<p>\u5de6\u9023\u63a5\u548c\u53f3\u9023\u63a5\u662fOracle\u6578\u64da\u5eab\u4e2d\u975e\u5e38\u91cd\u8981\u7684\u67e5\u8a62\u5de5\u5177\u3002\u4e86\u89e3\u5b83\u5011\u7684\u5340\u5225\u548c\u4f7f\u7528\u5834\u666f\uff0c\u53ef\u4ee5\u5e6b\u52a9\u958b\u767c\u8005\u66f4\u6709\u6548\u5730\u9032\u884c\u6578\u64da\u67e5\u8a62\u548c\u5206\u6790\u3002\u5728\u9078\u64c7\u4f7f\u7528\u54ea\u7a2e\u9023\u63a5\u6642\uff0c\u61c9\u6839\u64da\u5177\u9ad4\u9700\u6c42\u4f86\u6c7a\u5b9a\uff0c\u4ee5\u78ba\u4fdd\u67e5\u8a62\u7d50\u679c\u7684\u5b8c\u6574\u6027\u548c\u6e96\u78ba\u6027\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u6216\u5176\u4ed6\u6280\u8853\u554f\u984c\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\uff0c\u7279\u5225\u662f\u6211\u5011\u7684<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u89e3\u6c7a\u65b9\u6848\uff0c\u70ba\u60a8\u7684\u696d\u52d9\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3Oracle\u6578\u64da\u5eab\u4e2d\u7684\u5de6\u9023\u63a5\u8207\u53f3\u9023\u63a5\u7684\u5340\u5225\uff0c\u638c\u63e1\u6578\u64da\u67e5\u8a62\u6280\u5de7\uff0c\u63d0\u5347\u6578\u64da\u8655\u7406\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-95454","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95454","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=95454"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95454\/revisions"}],"predecessor-version":[{"id":95455,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95454\/revisions\/95455"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=95454"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=95454"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=95454"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}