{"id":95972,"date":"2024-10-20T05:32:14","date_gmt":"2024-10-19T21:32:14","guid":{"rendered":"https:\/\/server.hk\/cnblog\/95972\/"},"modified":"2024-10-20T05:32:15","modified_gmt":"2024-10-19T21:32:15","slug":"oracle%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e6%99%82%e9%96%93%e8%99%95%e7%90%86%e7%9a%84%e5%af%a6%e9%9a%9b%e6%93%8d%e4%bd%9c%e6%ad%a5%e9%a9%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/95972\/","title":{"rendered":"Oracle\u6578\u64da\u5eab\u4e2d\u7684\u6642\u9593\u8655\u7406\u7684\u5be6\u969b\u64cd\u4f5c\u6b65\u9a5f"},"content":{"rendered":"<h1 id=\"oracle%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e6%99%82%e9%96%93%e8%99%95%e7%90%86%e7%9a%84%e5%af%a6%e9%9a%9b%e6%93%8d%e4%bd%9c%e6%ad%a5%e9%a9%9f-JRwKUAmPCr\">Oracle\u6578\u64da\u5eab\u4e2d\u7684\u6642\u9593\u8655\u7406\u7684\u5be6\u969b\u64cd\u4f5c\u6b65\u9a5f<\/h1>\n<p>\u5728\u73fe\u4ee3\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u6642\u9593\u8655\u7406\u662f\u4e00\u500b\u81f3\u95dc\u91cd\u8981\u7684\u65b9\u9762\u3002Oracle\u6578\u64da\u5eab\u63d0\u4f9b\u4e86\u591a\u7a2e\u529f\u80fd\u4f86\u8655\u7406\u6642\u9593\u548c\u65e5\u671f\u6578\u64da\uff0c\u9019\u4e9b\u529f\u80fd\u5c0d\u65bc\u6578\u64da\u5206\u6790\u3001\u5831\u544a\u548c\u696d\u52d9\u908f\u8f2f\u7684\u5be6\u73fe\u81f3\u95dc\u91cd\u8981\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u5728Oracle\u6578\u64da\u5eab\u4e2d\u9032\u884c\u6642\u9593\u8655\u7406\u7684\u5be6\u969b\u64cd\u4f5c\u6b65\u9a5f\uff0c\u5e6b\u52a9\u7528\u6236\u66f4\u597d\u5730\u7406\u89e3\u548c\u61c9\u7528\u9019\u4e9b\u529f\u80fd\u3002<\/p>\n<h2 id=\"1-oracle%e4%b8%ad%e7%9a%84%e6%97%a5%e6%9c%9f%e5%92%8c%e6%99%82%e9%96%93%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b-JRwKUAmPCr\">1. Oracle\u4e2d\u7684\u65e5\u671f\u548c\u6642\u9593\u6578\u64da\u985e\u578b<\/h2>\n<p>\u5728Oracle\u6578\u64da\u5eab\u4e2d\uff0c\u4e3b\u8981\u6709\u4ee5\u4e0b\u5e7e\u7a2e\u65e5\u671f\u548c\u6642\u9593\u6578\u64da\u985e\u578b\uff1a<\/p>\n<ul>\n<li><strong>DATE<\/strong>: \u5132\u5b58\u65e5\u671f\u548c\u6642\u9593\uff0c\u7cbe\u78ba\u5230\u79d2\u3002<\/li>\n<li><strong>TIMESTAMP<\/strong>: \u5132\u5b58\u65e5\u671f\u548c\u6642\u9593\uff0c\u7cbe\u78ba\u5230\u5fae\u79d2\u3002<\/li>\n<li><strong>INTERVAL<\/strong>: \u7528\u65bc\u8868\u793a\u6642\u9593\u9593\u9694\u3002<\/li>\n<\/ul>\n<p>\u9019\u4e9b\u6578\u64da\u985e\u578b\u7684\u9078\u64c7\u53d6\u6c7a\u65bc\u5177\u9ad4\u7684\u61c9\u7528\u9700\u6c42\u3002\u4f8b\u5982\uff0c\u5982\u679c\u9700\u8981\u9ad8\u7cbe\u5ea6\u7684\u6642\u9593\u6233\uff0c\u5247\u61c9\u4f7f\u7528TIMESTAMP\u985e\u578b\u3002<\/p>\n<h2 id=\"2-%e5%89%b5%e5%bb%ba%e8%a1%a8%e6%a0%bc%e4%b8%a6%e6%8f%92%e5%85%a5%e6%99%82%e9%96%93%e6%95%b8%e6%93%9a-JRwKUAmPCr\">2. \u5275\u5efa\u8868\u683c\u4e26\u63d2\u5165\u6642\u9593\u6578\u64da<\/h2>\n<p>\u9996\u5148\uff0c\u6211\u5011\u9700\u8981\u5275\u5efa\u4e00\u500b\u8868\u683c\u4f86\u5132\u5b58\u6642\u9593\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u5275\u5efa\u4e00\u500b\u5305\u542b\u65e5\u671f\u548c\u6642\u9593\u7684\u8868\u683c\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>CREATE TABLE events (\n    event_id NUMBER PRIMARY KEY,\n    event_name VARCHAR2(100),\n    event_date DATE,\n    event_timestamp TIMESTAMP\n);<\/code><\/pre>\n<p>\u63a5\u4e0b\u4f86\uff0c\u6211\u5011\u53ef\u4ee5\u63d2\u5165\u4e00\u4e9b\u6578\u64da\uff1a<\/p>\n<pre><code>INSERT INTO events (event_id, event_name, event_date, event_timestamp)\nVALUES (1, '\u65b0\u5e74\u6d3e\u5c0d', TO_DATE('2023-01-01', 'YYYY-MM-DD'), SYSTIMESTAMP);<\/code><\/pre>\n<h2 id=\"3-%e6%9f%a5%e8%a9%a2%e6%99%82%e9%96%93%e6%95%b8%e6%93%9a-JRwKUAmPCr\">3. \u67e5\u8a62\u6642\u9593\u6578\u64da<\/h2>\n<p>\u67e5\u8a62\u6642\u9593\u6578\u64da\u6642\uff0c\u53ef\u4ee5\u4f7f\u7528\u591a\u7a2e\u51fd\u6578\u4f86\u683c\u5f0f\u5316\u548c\u64cd\u4f5c\u65e5\u671f\u3002\u4f8b\u5982\uff0c\u4f7f\u7528TO_CHAR\u51fd\u6578\u4f86\u683c\u5f0f\u5316\u65e5\u671f\uff1a<\/p>\n<pre><code>SELECT event_name, TO_CHAR(event_date, 'YYYY-MM-DD') AS formatted_date\nFROM events;<\/code><\/pre>\n<p>\u6b64\u5916\uff0c\u9084\u53ef\u4ee5\u4f7f\u7528SYSDATE\u51fd\u6578\u4f86\u7372\u53d6\u7576\u524d\u7cfb\u7d71\u6642\u9593\uff1a<\/p>\n<pre><code>SELECT event_name, event_date, SYSDATE AS current_time\nFROM events;<\/code><\/pre>\n<h2 id=\"4-%e6%99%82%e9%96%93%e8%a8%88%e7%ae%97-JRwKUAmPCr\">4. \u6642\u9593\u8a08\u7b97<\/h2>\n<p>\u5728Oracle\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528INTERVAL\u985e\u578b\u9032\u884c\u6642\u9593\u8a08\u7b97\u3002\u4f8b\u5982\uff0c\u8a08\u7b97\u4e8b\u4ef6\u8ddd\u96e2\u7576\u524d\u6642\u9593\u7684\u5929\u6578\uff1a<\/p>\n<pre><code>SELECT event_name, event_date, \n       (event_date - SYSDATE) AS days_until_event\nFROM events;<\/code><\/pre>\n<p>\u9019\u5c07\u8fd4\u56de\u6bcf\u500b\u4e8b\u4ef6\u8ddd\u96e2\u7576\u524d\u6642\u9593\u7684\u5929\u6578\u3002<\/p>\n<h2 id=\"5-%e4%bd%bf%e7%94%a8pl-sql%e9%80%b2%e8%a1%8c%e6%99%82%e9%96%93%e8%99%95%e7%90%86-JRwKUAmPCr\">5. \u4f7f\u7528PL\/SQL\u9032\u884c\u6642\u9593\u8655\u7406<\/h2>\n<p>PL\/SQL\u662f\u4e00\u7a2e\u5f37\u5927\u7684\u7de8\u7a0b\u8a9e\u8a00\uff0c\u53ef\u4ee5\u7528\u65bc\u9032\u884c\u66f4\u8907\u96dc\u7684\u6642\u9593\u8655\u7406\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684PL\/SQL\u7bc4\u4f8b\uff0c\u8a08\u7b97\u6240\u6709\u4e8b\u4ef6\u7684\u5269\u9918\u5929\u6578\uff1a<\/p>\n<pre><code>DECLARE\n    v_days_until_event NUMBER;\nBEGIN\n    FOR rec IN (SELECT event_name, event_date FROM events) LOOP\n        v_days_until_event := rec.event_date - SYSDATE;\n        DBMS_OUTPUT.PUT_LINE('\u4e8b\u4ef6: ' || rec.event_name || ' \u5269\u9918\u5929\u6578: ' || v_days_until_event);\n    END LOOP;\nEND;<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-JRwKUAmPCr\">\u7e3d\u7d50<\/h2>\n<p>\u5728Oracle\u6578\u64da\u5eab\u4e2d\uff0c\u6642\u9593\u8655\u7406\u662f\u4e00\u500b\u91cd\u8981\u7684\u529f\u80fd\uff0c\u6d89\u53ca\u5230\u65e5\u671f\u548c\u6642\u9593\u7684\u5b58\u5132\u3001\u67e5\u8a62\u548c\u8a08\u7b97\u3002\u901a\u904e\u4f7f\u7528\u5408\u9069\u7684\u6578\u64da\u985e\u578b\u548c\u51fd\u6578\uff0c\u7528\u6236\u53ef\u4ee5\u6709\u6548\u5730\u7ba1\u7406\u548c\u64cd\u4f5c\u6642\u9593\u6578\u64da\u3002\u7121\u8ad6\u662f\u5275\u5efa\u8868\u683c\u3001\u63d2\u5165\u6578\u64da\uff0c\u9084\u662f\u9032\u884c\u67e5\u8a62\u548c\u8a08\u7b97\uff0cOracle\u90fd\u63d0\u4f9b\u4e86\u5f37\u5927\u7684\u652f\u6301\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4f86\u904b\u884c\u60a8\u7684Oracle\u6578\u64da\u5eab\uff0cServer.HK\u63d0\u4f9b\u4e86\u591a\u7a2e\u9078\u64c7\uff0c\u6eff\u8db3\u4e0d\u540c\u9700\u6c42\u7684\u7528\u6236\u3002\u7121\u8ad6\u662f\u5c0f\u578b\u4f01\u696d\u9084\u662f\u5927\u578b\u4f01\u696d\uff0c\u6211\u5011\u7684 <a href=\"https:\/\/server.hk\">\u4e91\u670d\u52a1\u5668<\/a> \u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u6027\u80fd\u548c\u5b89\u5168\u7684\u74b0\u5883\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3Oracle\u6578\u64da\u5eab\u4e2d\u6642\u9593\u8655\u7406\u7684\u5be6\u969b\u64cd\u4f5c\u6b65\u9a5f\uff0c\u638c\u63e1\u65e5\u671f\u548c\u6642\u9593\u7684\u7ba1\u7406\u8207\u67e5\u8a62\u6280\u5de7\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-95972","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95972","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=95972"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95972\/revisions"}],"predecessor-version":[{"id":95973,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95972\/revisions\/95973"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=95972"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=95972"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=95972"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}