{"id":160671,"date":"2024-11-04T00:02:18","date_gmt":"2024-11-03T16:02:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/160671\/"},"modified":"2024-11-04T00:02:19","modified_gmt":"2024-11-03T16:02:19","slug":"postgresql%e6%95%99%e7%a8%8bpostgresql-%e9%81%8b%e7%ae%97%e7%ac%a6","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/160671\/","title":{"rendered":"POSTGRESQL\u6559\u7a0bPostgreSQL \u904b\u7b97\u7b26"},"content":{"rendered":"<h1 id=\"postgresql%e6%95%99%e7%a8%8b%ef%bc%9apostgresql-%e9%81%8b%e7%ae%97%e7%ac%a6-WTHKJMQXan\">PostgreSQL\u6559\u7a0b\uff1aPostgreSQL \u904b\u7b97\u7b26<\/h1>\n<p>PostgreSQL \u662f\u4e00\u500b\u5f37\u5927\u7684\u958b\u6e90\u95dc\u806f\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\uff0c\u5ee3\u6cdb\u61c9\u7528\u65bc\u5404\u7a2e\u61c9\u7528\u7a0b\u5e8f\u4e2d\u3002\u5b83\u652f\u6301\u591a\u7a2e\u6578\u64da\u985e\u578b\u548c\u904b\u7b97\u7b26\uff0c\u4f7f\u5f97\u6578\u64da\u64cd\u4f5c\u66f4\u52a0\u9748\u6d3b\u548c\u9ad8\u6548\u3002\u5728\u9019\u7bc7\u6587\u7ae0\u4e2d\uff0c\u6211\u5011\u5c07\u6df1\u5165\u63a2\u8a0e PostgreSQL \u4e2d\u7684\u904b\u7b97\u7b26\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u793a\u4f8b\u4f86\u5e6b\u52a9\u60a8\u66f4\u597d\u5730\u7406\u89e3\u5982\u4f55\u4f7f\u7528\u9019\u4e9b\u904b\u7b97\u7b26\u3002<\/p>\n<h2 id=\"%e9%81%8b%e7%ae%97%e7%ac%a6%e7%9a%84%e9%a1%9e%e5%9e%8b-WTHKJMQXan\">\u904b\u7b97\u7b26\u7684\u985e\u578b<\/h2>\n<p>\u5728 PostgreSQL \u4e2d\uff0c\u904b\u7b97\u7b26\u53ef\u4ee5\u5206\u70ba\u5e7e\u500b\u4e3b\u8981\u985e\u578b\uff0c\u5305\u62ec\u7b97\u8853\u904b\u7b97\u7b26\u3001\u6bd4\u8f03\u904b\u7b97\u7b26\u3001\u908f\u8f2f\u904b\u7b97\u7b26\u548c\u4f4d\u904b\u7b97\u7b26\u3002\u6bcf\u7a2e\u985e\u578b\u7684\u904b\u7b97\u7b26\u90fd\u6709\u5176\u7279\u5b9a\u7684\u7528\u9014\u548c\u529f\u80fd\u3002<\/p>\n<h3 id=\"1-%e7%ae%97%e8%a1%93%e9%81%8b%e7%ae%97%e7%ac%a6-WTHKJMQXan\">1. \u7b97\u8853\u904b\u7b97\u7b26<\/h3>\n<p>\u7b97\u8853\u904b\u7b97\u7b26\u7528\u65bc\u6578\u503c\u8a08\u7b97\uff0c\u4e3b\u8981\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><code>+<\/code>\uff1a\u52a0\u6cd5<\/li>\n<li><code>-<\/code>\uff1a\u6e1b\u6cd5<\/li>\n<li><code>*<\/code>\uff1a\u4e58\u6cd5<\/li>\n<li><code>\/<\/code>\uff1a\u9664\u6cd5<\/li>\n<li><code>%<\/code>\uff1a\u53d6\u9918\u6578<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b SQL \u67e5\u8a62\u4f86\u8a08\u7b97\u5169\u500b\u6578\u5b57\u7684\u548c\uff1a<\/p>\n<pre><code>SELECT 10 + 5 AS sum;<\/code><\/pre>\n<h3 id=\"2-%e6%af%94%e8%bc%83%e9%81%8b%e7%ae%97%e7%ac%a6-WTHKJMQXan\">2. \u6bd4\u8f03\u904b\u7b97\u7b26<\/h3>\n<p>\u6bd4\u8f03\u904b\u7b97\u7b26\u7528\u65bc\u6bd4\u8f03\u5169\u500b\u503c\uff0c\u4e3b\u8981\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><code>=<\/code>\uff1a\u7b49\u65bc<\/li>\n<li><code>!=<\/code> \u6216 <code>&lt;&gt;<\/code>\uff1a\u4e0d\u7b49\u65bc<\/li>\n<li><code>&gt;<\/code>\uff1a\u5927\u65bc<\/li>\n<li><code>&lt;<\/code>\uff1a\u5c0f\u65bc<\/li>\n<li><code>&gt;=<\/code>\uff1a\u5927\u65bc\u7b49\u65bc<\/li>\n<li><code>&lt;=<\/code>\uff1a\u5c0f\u65bc\u7b49\u65bc<\/li>\n<\/ul>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528\u6bd4\u8f03\u904b\u7b97\u7b26\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT * FROM employees WHERE salary &gt; 50000;<\/code><\/pre>\n<h3 id=\"3-%e9%82%8f%e8%bc%af%e9%81%8b%e7%ae%97%e7%ac%a6-WTHKJMQXan\">3. \u908f\u8f2f\u904b\u7b97\u7b26<\/h3>\n<p>\u908f\u8f2f\u904b\u7b97\u7b26\u7528\u65bc\u7d44\u5408\u591a\u500b\u689d\u4ef6\uff0c\u4e3b\u8981\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><code>AND<\/code>\uff1a\u8207<\/li>\n<li><code>OR<\/code>\uff1a\u6216<\/li>\n<li><code>NOT<\/code>\uff1a\u975e<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\u4f86\u9078\u64c7\u6eff\u8db3\u591a\u500b\u689d\u4ef6\u7684\u8a18\u9304\uff1a<\/p>\n<pre><code>SELECT * FROM employees WHERE salary &gt; 50000 AND department = 'Sales';<\/code><\/pre>\n<h3 id=\"4-%e4%bd%8d%e9%81%8b%e7%ae%97%e7%ac%a6-WTHKJMQXan\">4. \u4f4d\u904b\u7b97\u7b26<\/h3>\n<p>\u4f4d\u904b\u7b97\u7b26\u7528\u65bc\u5c0d\u4f4d\u9032\u884c\u64cd\u4f5c\uff0c\u4e3b\u8981\u5305\u62ec\uff1a<\/p>\n<ul>\n<li><code>&amp;<\/code>\uff1a\u6309\u4f4d\u8207<\/li>\n<li><code>|<\/code>\uff1a\u6309\u4f4d\u6216<\/li>\n<li><code>^<\/code>\uff1a\u6309\u4f4d\u7570\u6216<\/li>\n<li><code>~<\/code>\uff1a\u6309\u4f4d\u975e<\/li>\n<\/ul>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528\u4f4d\u904b\u7b97\u7b26\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT 5 &amp; 3 AS bitwise_and;<\/code><\/pre>\n<h2 id=\"%e8%87%aa%e5%ae%9a%e7%be%a9%e9%81%8b%e7%ae%97%e7%ac%a6-WTHKJMQXan\">\u81ea\u5b9a\u7fa9\u904b\u7b97\u7b26<\/h2>\n<p>PostgreSQL \u5141\u8a31\u7528\u6236\u5275\u5efa\u81ea\u5b9a\u7fa9\u904b\u7b97\u7b26\uff0c\u4ee5\u6eff\u8db3\u7279\u5b9a\u9700\u6c42\u3002\u9019\u53ef\u4ee5\u901a\u904e\u4f7f\u7528 <code>CREATE OPERATOR<\/code> \u8a9e\u53e5\u4f86\u5be6\u73fe\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>CREATE OPERATOR + (\n    LEFTARG = integer,\n    RIGHTARG = integer,\n    PROCEDURE = my_add_function\n);<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0c\u6211\u5011\u5275\u5efa\u4e86\u4e00\u500b\u65b0\u7684\u52a0\u6cd5\u904b\u7b97\u7b26\uff0c\u4e26\u6307\u5b9a\u4e86\u5176\u64cd\u4f5c\u7684\u6578\u64da\u985e\u578b\u548c\u76f8\u61c9\u7684\u8655\u7406\u51fd\u6578\u3002<\/p>\n<h2 id=\"%e7%b5%90%e8%ab%96-WTHKJMQXan\">\u7d50\u8ad6<\/h2>\n<p>PostgreSQL \u7684\u904b\u7b97\u7b26\u70ba\u6578\u64da\u64cd\u4f5c\u63d0\u4f9b\u4e86\u5f37\u5927\u7684\u652f\u6301\uff0c\u7121\u8ad6\u662f\u9032\u884c\u57fa\u672c\u7684\u6578\u5b78\u8a08\u7b97\uff0c\u9084\u662f\u8907\u96dc\u7684\u908f\u8f2f\u5224\u65b7\uff0c\u904b\u7b97\u7b26\u90fd\u80fd\u5920\u5e6b\u52a9\u958b\u767c\u8005\u9ad8\u6548\u5730\u8655\u7406\u6578\u64da\u3002\u4e86\u89e3\u9019\u4e9b\u904b\u7b97\u7b26\u7684\u4f7f\u7528\u65b9\u6cd5\uff0c\u5c07\u6709\u52a9\u65bc\u60a8\u5728 PostgreSQL \u4e2d\u9032\u884c\u66f4\u9ad8\u6548\u7684\u6578\u64da\u67e5\u8a62\u548c\u64cd\u4f5c\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4f86\u904b\u884c\u60a8\u7684 PostgreSQL \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\u9805\u76ee\u9084\u662f\u5927\u578b\u61c9\u7528\uff0c\u6211\u5011\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a> \u90fd\u80fd\u70ba\u60a8\u63d0\u4f9b\u7a69\u5b9a\u7684\u652f\u6301\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22PostgreSQL\u904b\u7b97\u7b26\u7684\u5168\u9762\u6559\u7a0b\uff0c\u5b78\u7fd2\u5982\u4f55\u6709\u6548\u4f7f\u7528\u5404\u7a2e\u904b\u7b97\u7b26\u4f86\u512a\u5316\u6578\u64da\u67e5\u8a62\u548c\u64cd\u4f5c\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-160671","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/160671","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=160671"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/160671\/revisions"}],"predecessor-version":[{"id":160672,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/160671\/revisions\/160672"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=160671"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=160671"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=160671"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}