{"id":195759,"date":"2024-11-13T17:40:18","date_gmt":"2024-11-13T09:40:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/195759\/"},"modified":"2024-11-13T17:40:19","modified_gmt":"2024-11-13T09:40:19","slug":"%e5%9c%a8oracle%e6%99%82%e9%96%93%e6%87%89%e7%94%a8%e4%b8%ad%e5%a6%82%e4%bd%95%e8%bd%89%e6%8f%9b%e5%87%bd%e6%95%b8","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/195759\/","title":{"rendered":"\u5728Oracle\u6642\u9593\u61c9\u7528\u4e2d\u5982\u4f55\u8f49\u63db\u51fd\u6578"},"content":{"rendered":"<h1 id=\"%e5%9c%a8oracle%e6%99%82%e9%96%93%e6%87%89%e7%94%a8%e4%b8%ad%e5%a6%82%e4%bd%95%e8%bd%89%e6%8f%9b%e5%87%bd%e6%95%b8-zxCmejdGtv\">\u5728Oracle\u6642\u9593\u61c9\u7528\u4e2d\u5982\u4f55\u8f49\u63db\u51fd\u6578<\/h1>\n<p>\u5728Oracle\u6578\u64da\u5eab\u4e2d\uff0c\u6642\u9593\u548c\u65e5\u671f\u7684\u8655\u7406\u662f\u975e\u5e38\u91cd\u8981\u7684\uff0c\u5c24\u5176\u662f\u5728\u9032\u884c\u6578\u64da\u5206\u6790\u548c\u5831\u544a\u6642\u3002Oracle\u63d0\u4f9b\u4e86\u591a\u7a2e\u51fd\u6578\u4f86\u8655\u7406\u6642\u9593\u548c\u65e5\u671f\u7684\u8f49\u63db\uff0c\u9019\u4e9b\u51fd\u6578\u53ef\u4ee5\u5e6b\u52a9\u7528\u6236\u5c07\u4e0d\u540c\u683c\u5f0f\u7684\u6642\u9593\u6578\u64da\u8f49\u63db\u70ba\u6240\u9700\u7684\u683c\u5f0f\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5728Oracle\u4e2d\u5982\u4f55\u4f7f\u7528\u9019\u4e9b\u8f49\u63db\u51fd\u6578\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u793a\u4f8b\u3002<\/p>\n<h2 id=\"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-zxCmejdGtv\">Oracle\u4e2d\u7684\u65e5\u671f\u548c\u6642\u9593\u6578\u64da\u985e\u578b<\/h2>\n<p>\u5728Oracle\u4e2d\uff0c\u4e3b\u8981\u6709\u5169\u7a2e\u65e5\u671f\u548c\u6642\u9593\u6578\u64da\u985e\u578b\uff1a<code>DATE<\/code>\u548c<code>TIMESTAMP<\/code>\u3002<\/p>\n<ul>\n<li><code>DATE<\/code>\uff1a\u6b64\u6578\u64da\u985e\u578b\u5305\u542b\u5e74\u3001\u6708\u3001\u65e5\u3001\u6642\u3001\u5206\u3001\u79d2\u7684\u8cc7\u8a0a\uff0c\u7cbe\u78ba\u5230\u79d2\u3002<\/li>\n<li><code>TIMESTAMP<\/code>\uff1a\u6b64\u6578\u64da\u985e\u578b\u9664\u4e86\u5305\u542b<code>DATE<\/code>\u7684\u6240\u6709\u8cc7\u8a0a\u5916\uff0c\u9084\u53ef\u4ee5\u5305\u542b\u5c0f\u6578\u79d2\uff0c\u63d0\u4f9b\u66f4\u9ad8\u7684\u7cbe\u78ba\u5ea6\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%b8%b8%e7%94%a8%e7%9a%84%e6%97%a5%e6%9c%9f%e8%bd%89%e6%8f%9b%e5%87%bd%e6%95%b8-zxCmejdGtv\">\u5e38\u7528\u7684\u65e5\u671f\u8f49\u63db\u51fd\u6578<\/h2>\n<p>Oracle\u63d0\u4f9b\u4e86\u5e7e\u500b\u91cd\u8981\u7684\u51fd\u6578\u4f86\u9032\u884c\u65e5\u671f\u548c\u6642\u9593\u7684\u8f49\u63db\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u7528\u7684\u51fd\u6578\uff1a<\/p>\n<h3 id=\"1-to_date-zxCmejdGtv\">1. TO_DATE<\/h3>\n<p><code>TO_DATE<\/code>\u51fd\u6578\u7528\u65bc\u5c07\u5b57\u7b26\u4e32\u8f49\u63db\u70ba\u65e5\u671f\u683c\u5f0f\u3002\u5176\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>TO_DATE('string', 'format')<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07\u5b57\u7b26\u4e32&#8217;2023-10-01&#8217;\u8f49\u63db\u70ba\u65e5\u671f\u683c\u5f0f\uff1a<\/p>\n<pre><code>SELECT TO_DATE('2023-10-01', 'YYYY-MM-DD') FROM dual;<\/code><\/pre>\n<h3 id=\"2-to_char-zxCmejdGtv\">2. TO_CHAR<\/h3>\n<p><code>TO_CHAR<\/code>\u51fd\u6578\u7528\u65bc\u5c07\u65e5\u671f\u8f49\u63db\u70ba\u5b57\u7b26\u4e32\u683c\u5f0f\u3002\u5176\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>TO_CHAR(date, 'format')<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07\u7576\u524d\u65e5\u671f\u8f49\u63db\u70ba&#8217;YYYY\/MM\/DD&#8217;\u683c\u5f0f\uff1a<\/p>\n<pre><code>SELECT TO_CHAR(SYSDATE, 'YYYY\/MM\/DD') FROM dual;<\/code><\/pre>\n<h3 id=\"3-extract-zxCmejdGtv\">3. EXTRACT<\/h3>\n<p><code>EXTRACT<\/code>\u51fd\u6578\u7528\u65bc\u5f9e\u65e5\u671f\u4e2d\u63d0\u53d6\u7279\u5b9a\u7684\u90e8\u5206\uff0c\u5982\u5e74\u3001\u6708\u3001\u65e5\u7b49\u3002\u5176\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>EXTRACT(part FROM date)<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u63d0\u53d6\u7576\u524d\u65e5\u671f\u7684\u5e74\u4efd\uff1a<\/p>\n<pre><code>SELECT EXTRACT(YEAR FROM SYSDATE) FROM dual;<\/code><\/pre>\n<h3 id=\"4-add_months-zxCmejdGtv\">4. ADD_MONTHS<\/h3>\n<p><code>ADD_MONTHS<\/code>\u51fd\u6578\u7528\u65bc\u5728\u6307\u5b9a\u7684\u65e5\u671f\u4e0a\u6dfb\u52a0\u6216\u6e1b\u53bb\u6708\u4efd\u3002\u5176\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>ADD_MONTHS(date, n)<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5c07\u7576\u524d\u65e5\u671f\u52a0\u4e0a3\u500b\u6708\uff1a<\/p>\n<pre><code>SELECT ADD_MONTHS(SYSDATE, 3) FROM dual;<\/code><\/pre>\n<h2 id=\"%e5%af%a6%e9%9a%9b%e6%87%89%e7%94%a8%e7%a4%ba%e4%be%8b-zxCmejdGtv\">\u5be6\u969b\u61c9\u7528\u793a\u4f8b<\/h2>\n<p>\u5728\u5be6\u969b\u61c9\u7528\u4e2d\uff0c\u9019\u4e9b\u51fd\u6578\u53ef\u4ee5\u5e6b\u52a9\u7528\u6236\u9032\u884c\u5404\u7a2e\u65e5\u671f\u548c\u6642\u9593\u7684\u8a08\u7b97\u3002\u4f8b\u5982\uff0c\u5047\u8a2d\u6211\u5011\u9700\u8981\u67e5\u8a62\u67d0\u500b\u5ba2\u6236\u5728\u904e\u53bb\u4e00\u5e74\u5167\u7684\u8a02\u55ae\u6578\u91cf\uff0c\u6211\u5011\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT COUNT(*)\nFROM orders\nWHERE order_date &gt; ADD_MONTHS(SYSDATE, -12);<\/code><\/pre>\n<p>\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u904e\u53bb\u4e00\u5e74\u5167\u7684\u6240\u6709\u8a02\u55ae\u6578\u91cf\uff0c\u5229\u7528\u4e86<code>ADD_MONTHS<\/code>\u51fd\u6578\u4f86\u8a08\u7b97\u65e5\u671f\u7bc4\u570d\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-zxCmejdGtv\">\u7e3d\u7d50<\/h2>\n<p>\u5728Oracle\u4e2d\uff0c\u65e5\u671f\u548c\u6642\u9593\u7684\u8f49\u63db\u51fd\u6578\u662f\u6578\u64da\u8655\u7406\u4e2d\u4e0d\u53ef\u6216\u7f3a\u7684\u5de5\u5177\u3002\u901a\u904e\u4f7f\u7528<code>TO_DATE<\/code>\u3001<code>TO_CHAR<\/code>\u3001<code>EXTRACT<\/code>\u548c<code>ADD_MONTHS<\/code>\u7b49\u51fd\u6578\uff0c\u7528\u6236\u53ef\u4ee5\u9748\u6d3b\u5730\u8655\u7406\u548c\u8f49\u63db\u6642\u9593\u6578\u64da\uff0c\u4ee5\u6eff\u8db3\u4e0d\u540c\u7684\u9700\u6c42\u3002\u9019\u4e9b\u51fd\u6578\u4e0d\u50c5\u63d0\u9ad8\u4e86\u6578\u64da\u67e5\u8a62\u7684\u6548\u7387\uff0c\u9084\u80fd\u5e6b\u52a9\u7528\u6236\u66f4\u597d\u5730\u7406\u89e3\u548c\u5206\u6790\u6578\u64da\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc<code>VPS<\/code>\u3001<code>\u9999\u6e2fVPS<\/code>\u6216\u5176\u4ed6<code>\u4e91\u670d\u52a1\u5668<\/code>\u7684\u9700\u6c42\u611f\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9 <a href=\"https:\/\/server.hk\">Server.HK<\/a> \u7372\u53d6\u66f4\u591a\u8cc7\u8a0a\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u5728Oracle\u6642\u9593\u61c9\u7528\u4e2d\u4f7f\u7528\u8f49\u63db\u51fd\u6578\uff0c\u8f15\u9b06\u8655\u7406\u65e5\u671f\u548c\u6642\u9593\u683c\u5f0f\uff0c\u63d0\u5347\u6578\u64da\u7ba1\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-195759","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/195759","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=195759"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/195759\/revisions"}],"predecessor-version":[{"id":195760,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/195759\/revisions\/195760"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=195759"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=195759"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=195759"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}