{"id":5201,"date":"2024-11-14T11:50:33","date_gmt":"2024-11-14T03:50:33","guid":{"rendered":"https:\/\/fwq.ai\/blog\/5201\/"},"modified":"2024-11-14T11:50:33","modified_gmt":"2024-11-14T03:50:33","slug":"sql%e4%b8%adas%e5%9c%a8%e5%ad%97%e6%ae%b5%e7%9a%84%e7%94%a8%e6%b3%95","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/5201\/","title":{"rendered":"sql\u4e2das\u5728\u5b57\u6bb5\u7684\u7528\u6cd5"},"content":{"rendered":"<blockquote><p>\n  \u5728 sql \u4e2d\uff0cas \u5173\u952e\u5b57\u7528\u4e8e\u4e3a\u5b57\u6bb5\u6307\u5b9a\u522b\u540d\uff0c\u4f7f\u5176\u66f4\u7b80\u6d01\u3001\u907f\u514d\u51b2\u7a81\u3001\u66f4\u6539\u6570\u636e\u7c7b\u578b\u6216\u63d0\u9ad8\u53ef\u8bfb\u6027\u3002\u5b83\u53ef\u4ee5\u4e0e\u5b57\u6bb5\u4e00\u8d77\u4f7f\u7528\uff0c\u540e\u8ddf as \u548c\u65b0\u522b\u540d\uff0c\u4f8b\u5982\uff1aselect customer_id as id, customer_name as name from customers;\n<\/p><\/blockquote>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/202405\/24\/2024052420212159591.jpg\" class=\"aligncenter\" title=\"sql\u4e2das\u5728\u5b57\u6bb5\u7684\u7528\u6cd5\u63d2\u56fe\" alt=\"sql\u4e2das\u5728\u5b57\u6bb5\u7684\u7528\u6cd5\u63d2\u56fe\" \/><\/p>\n<p><strong>SQL \u4e2d AS \u5173\u952e\u5b57\u5728\u5b57\u6bb5\u4e2d\u7684\u7528\u6cd5<\/strong><\/p>\n<p>\u5728 SQL \u4e2d\uff0cAS \u5173\u952e\u5b57\u7528\u4e8e\u7ed9\u67e5\u8be2\u4e2d\u7684\u5b57\u6bb5\u8d77\u522b\u540d\u3002\u8fd9\u5728\u4ee5\u4e0b\u573a\u666f\u4e2d\u975e\u5e38\u6709\u7528\uff1a<\/p>\n<p><strong>\u7b80\u5316\u5b57\u6bb5\u540d<\/strong><\/p>\n<p>\u5f53\u5b57\u6bb5\u540d\u5f88\u957f\u6216\u96be\u4ee5\u7406\u89e3\u65f6\uff0c\u53ef\u4ee5\u4f7f\u7528 AS \u4e3a\u5176\u6307\u5b9a\u4e00\u4e2a\u66f4\u77ed\u3001\u66f4\u7b80\u6d01\u7684\u522b\u540d\uff0c\u4ece\u800c\u63d0\u9ad8\u67e5\u8be2\u7684\u53ef\u8bfb\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u3002<\/p>\n<p>\u4f8b\u5982\uff1a<\/p>\n<pre>SELECT customer_id AS ID, customer_name AS Name FROM customers;<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p><strong>\u907f\u514d\u5b57\u6bb5\u540d\u51b2\u7a81<\/strong><\/p>\n<p>\u5f53\u67e5\u8be2\u6765\u81ea\u4e0d\u540c\u8868\u4e2d\u7684\u5b57\u6bb5\u65f6\uff0c\u53ef\u80fd\u4f1a\u51fa\u73b0\u5b57\u6bb5\u540d\u51b2\u7a81\u3002\u4f7f\u7528 AS \u5173\u952e\u5b57\u53ef\u4ee5\u4e3a\u6bcf\u4e2a\u8868\u7684\u5b57\u6bb5\u6307\u5b9a\u4e0d\u540c\u7684\u522b\u540d\uff0c\u4ece\u800c\u89e3\u51b3\u51b2\u7a81\u3002<\/p>\n<p>\u4f8b\u5982\uff1a<\/p>\n<pre>SELECT c.customer_id AS CustomerID, o.order_id AS OrderID\nFROM customers c\nJOIN orders o ON c.customer_id = o.customer_id;<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p><strong>\u66f4\u6539\u5b57\u6bb5\u6570\u636e\u7c7b\u578b<\/strong><\/p>\n<p>\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u9700\u8981\u5c06\u5b57\u6bb5\u8f6c\u6362\u4e3a\u4e0d\u540c\u7684\u6570\u636e\u7c7b\u578b\u3002AS \u5173\u952e\u5b57\u53ef\u4ee5\u4e0e CAST() \u51fd\u6570\u7ed3\u5408\u4f7f\u7528\uff0c\u5728\u67e5\u8be2\u4e2d\u4e34\u65f6\u66f4\u6539\u5b57\u6bb5\u7684\u6570\u636e\u7c7b\u578b\u3002<\/p>\n<p>\u4f8b\u5982\uff1a<\/p>\n<pre>SELECT CAST(order_date AS DATE) AS DateOnly\nFROM orders;<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p><strong>\u63d0\u9ad8\u53ef\u8bfb\u6027<\/strong><\/p>\n<p>\u4f7f\u7528 AS \u5173\u952e\u5b57\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u7684\u53ef\u8bfb\u6027\uff0c\u56e0\u4e3a\u5b83\u5141\u8bb8\u4f7f\u7528\u66f4\u5177\u63cf\u8ff0\u6027\u7684\u522b\u540d\u6765\u8868\u793a\u5b57\u6bb5\u3002<\/p>\n<p>\u4f8b\u5982\uff1a<\/p>\n<pre>SELECT SUM(order_total) AS TotalSales\nFROM orders;<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p><strong>\u793a\u4f8b<\/strong><\/p>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e2a\u4f7f\u7528 AS \u5173\u952e\u5b57\u7684\u793a\u4f8b\u67e5\u8be2\uff1a<\/p>\n<pre>SELECT customer_id AS ID,\n       customer_name AS Name,\n       SUM(order_total) AS TotalSales\nFROM customers c\nJOIN orders o ON c.customer_id = o.customer_id\nGROUP BY customer_id, customer_name;<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p>\u5728\u8be5\u67e5\u8be2\u4e2d\uff0ccustomer_id\u3001customer_name \u548c order_total \u5b57\u6bb5\u5206\u522b\u88ab\u8d4b\u4e88\u4e86\u522b\u540d ID\u3001Name \u548c TotalSales\uff0c\u4ee5\u63d0\u9ad8\u67e5\u8be2\u7684\u53ef\u8bfb\u6027\u5e76\u7b80\u5316\u5176\u4f7f\u7528\u3002<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662fsql\u4e2das\u5728\u5b57\u6bb5\u7684\u7528\u6cd5\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u7f51\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5728 sql \u4e2d\uff0cas \u5173\u952e\u5b57\u7528\u4e8e\u4e3a\u5b57\u6bb5\u6307\u5b9a\u522b\u540d\uff0c\u4f7f\u5176\u66f4\u7b80\u6d01\u3001\u907f\u514d\u51b2\u7a81\u3001\u66f4\u6539\u6570\u636e\u7c7b\u578b\u6216\u63d0\u9ad8\u53ef\u8bfb\u6027\u3002\u5b83\u53ef\u4ee5\u4e0e\u5b57\u6bb5\u4e00\u8d77\u4f7f\u7528\uff0c\u540e\u8ddf as \u548c\u65b0\u522b\u540d\uff0c\u4f8b\u5982\uff1aselect customer_id as id, customer_name as name from customers; SQL \u4e2d AS \u5173\u952e\u5b57\u5728\u5b57\u6bb5\u4e2d\u7684\u7528\u6cd5 \u5728 SQL \u4e2d\uff0cAS \u5173\u952e\u5b57\u7528\u4e8e\u7ed9\u67e5\u8be2\u4e2d\u7684\u5b57\u6bb5\u8d77\u522b\u540d\u3002\u8fd9\u5728\u4ee5\u4e0b\u573a\u666f\u4e2d\u975e\u5e38\u6709\u7528\uff1a \u7b80\u5316\u5b57\u6bb5\u540d \u5f53\u5b57\u6bb5\u540d\u5f88\u957f\u6216\u96be\u4ee5\u7406\u89e3\u65f6\uff0c\u53ef\u4ee5\u4f7f\u7528 AS \u4e3a\u5176\u6307\u5b9a\u4e00\u4e2a\u66f4\u77ed\u3001\u66f4\u7b80\u6d01\u7684\u522b\u540d\uff0c\u4ece\u800c\u63d0\u9ad8\u67e5\u8be2\u7684\u53ef\u8bfb\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u3002 \u4f8b\u5982\uff1a SELECT customer_id AS ID, customer_name AS Name FROM customers; \u767b\u5f55\u540e\u590d\u5236 \u907f\u514d\u5b57\u6bb5\u540d\u51b2\u7a81 \u5f53\u67e5\u8be2\u6765\u81ea\u4e0d\u540c\u8868\u4e2d\u7684\u5b57\u6bb5\u65f6\uff0c\u53ef\u80fd\u4f1a\u51fa\u73b0\u5b57\u6bb5\u540d\u51b2\u7a81\u3002\u4f7f\u7528 AS \u5173\u952e\u5b57\u53ef\u4ee5\u4e3a\u6bcf\u4e2a\u8868\u7684\u5b57\u6bb5\u6307\u5b9a\u4e0d\u540c\u7684\u522b\u540d\uff0c\u4ece\u800c\u89e3\u51b3\u51b2\u7a81\u3002 \u4f8b\u5982\uff1a SELECT c.customer_id AS CustomerID, o.order_id AS OrderID FROM customers c JOIN orders o [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-5201","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5201","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=5201"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5201\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=5201"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=5201"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=5201"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}