{"id":5752,"date":"2024-11-14T08:12:59","date_gmt":"2024-11-14T00:12:59","guid":{"rendered":"https:\/\/fwq.ai\/blog\/5752\/"},"modified":"2024-11-14T08:12:59","modified_gmt":"2024-11-14T00:12:59","slug":"oracle%e5%ad%90%e6%9f%a5%e8%af%a2%e6%80%8e%e4%b9%88%e5%85%b3%e9%97%ad","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/5752\/","title":{"rendered":"oracle\u5b50\u67e5\u8be2\u600e\u4e48\u5173\u95ed"},"content":{"rendered":"

\n \u5173\u95ed\u5b50\u67e5\u8be2\u53ef\u4ee5\u63d0\u9ad8 oracle \u590d\u6742\u67e5\u8be2\u7684\u6027\u80fd\uff1a\u4f7f\u7528 join \u5c06\u5b50\u67e5\u8be2\u91cd\u5199\u4e3a join\u3002\u5728\u5408\u9002\u7684\u60c5\u51b5\u4e0b\u4f7f\u7528 exists \u8fd0\u7b97\u7b26\u3002\u521b\u5efa\u7269\u5316\u89c6\u56fe\u6765\u5b58\u50a8\u5b50\u67e5\u8be2\u7ed3\u679c\u3002\u4f7f\u7528 common table expressions (cte)\u3002\u4e3a\u8fde\u63a5\u5b57\u6bb5\u5efa\u7acb\u7d22\u5f15\u3002\u5c06\u5927\u8868\u5206\u533a\u4ee5\u63d0\u9ad8\u6548\u7387\u3002\u4f18\u5316\u5b50\u67e5\u8be2\u4ee5\u63d0\u9ad8\u6027\u80fd\u3002\n<\/p><\/blockquote>\n

\"oracle\u5b50\u67e5\u8be2\u600e\u4e48\u5173\u95ed\u63d2\u56fe\"<\/p>\n

Oracle \u5b50\u67e5\u8be2\u6027\u80fd\u4f18\u5316\uff1a\u5173\u95ed\u5b50\u67e5\u8be2<\/strong><\/p>\n

Oracle \u4e2d\u7684\u5b50\u67e5\u8be2\u53ef\u4ee5\u63d0\u9ad8\u590d\u6742\u67e5\u8be2\u7684\u6548\u7387\uff0c\u4f46\u5982\u679c\u4f7f\u7528\u4e0d\u5f53\uff0c\u4e5f\u4f1a\u5bfc\u81f4\u6027\u80fd\u95ee\u9898\u3002\u5173\u95ed\u5b50\u67e5\u8be2\u53ef\u4ee5\u663e\u8457\u63d0\u9ad8\u6027\u80fd\uff0c\u4e0b\u9762\u4ecb\u7ecd\u5173\u95ed\u5b50\u67e5\u8be2\u7684\u51e0\u79cd\u65b9\u6cd5\uff1a<\/p>\n

1. \u4f7f\u7528 JOIN<\/strong><\/p>\n

\u5c06\u5b50\u67e5\u8be2\u91cd\u5199\u4e3a JOIN \u53ef\u4ee5\u6d88\u9664\u5b50\u67e5\u8be2\uff0c\u4ece\u800c\u63d0\u9ad8\u6027\u80fd\u3002\u4f8b\u5982\uff1a<\/p>\n

SELECT * FROM customers WHERE customer_id IN (SELECT customer_id FROM orders);<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u53ef\u4ee5\u91cd\u5199\u4e3a\uff1a<\/p>\n
SELECT * FROM customers c JOIN orders o ON c.customer_id = o.customer_id;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
2. \u4f7f\u7528 EXISTS<\/strong><\/p>\n
\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u53ef\u4ee5\u4f7f\u7528 EXISTS \u8fd0\u7b97\u7b26\u4ee3\u66ff\u5b50\u67e5\u8be2\u3002\u4f8b\u5982\uff1a<\/p>\n
SELECT * FROM customers WHERE EXISTS (SELECT 1 FROM orders WHERE customer_id = customers.customer_id);<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u53ef\u4ee5\u91cd\u5199\u4e3a\uff1a<\/p>\n
SELECT * FROM customers WHERE customer_id IN (SELECT customer_id FROM orders);<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
3. \u4f7f\u7528 Materialized Views<\/strong><\/p>\n
\u7269\u5316\u89c6\u56fe\u662f\u9884\u5148\u8ba1\u7b97\u597d\u7684\u67e5\u8be2\u7ed3\u679c\uff0c\u53ef\u4ee5\u63d0\u9ad8\u540e\u7eed\u67e5\u8be2\u7684\u6027\u80fd\u3002\u5982\u679c\u5b50\u67e5\u8be2\u7ecf\u5e38\u4f7f\u7528\uff0c\u53ef\u4ee5\u521b\u5efa\u7269\u5316\u89c6\u56fe\u6765\u5b58\u50a8\u5176\u7ed3\u679c\uff0c\u4ece\u800c\u907f\u514d\u5728\u6bcf\u6b21\u67e5\u8be2\u65f6\u91cd\u65b0\u8ba1\u7b97\u3002<\/p>\n
4. \u4f7f\u7528 Common Table Expressions (CTE)<\/strong><\/p>\n
CTE \u5141\u8bb8\u5c06\u590d\u6742\u67e5\u8be2\u7ed3\u679c\u4e34\u65f6\u5b58\u50a8\u5230\u4e34\u65f6\u8868\u4e2d\uff0c\u4ece\u800c\u63d0\u9ad8\u6027\u80fd\u3002\u4f8b\u5982\uff1a<\/p>\n
WITH order_counts AS (\n    SELECT customer_id, COUNT(*) AS order_count FROM orders GROUP BY customer_id\n)\nSELECT * FROM customers c JOIN order_counts oc ON c.customer_id = oc.customer_id;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
5. \u4f7f\u7528\u7d22\u5f15<\/strong><\/p>\n
\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u67e5\u8be2\u901f\u5ea6\u3002\u5982\u679c\u5b50\u67e5\u8be2\u4f7f\u7528\u8fde\u63a5\u5b57\u6bb5\uff0c\u786e\u4fdd\u5bf9\u8fd9\u4e9b\u5b57\u6bb5\u5efa\u7acb\u7d22\u5f15\u4ee5\u63d0\u9ad8\u6027\u80fd\u3002<\/p>\n
6. \u4f7f\u7528\u5206\u533a<\/strong><\/p>\n
\u5982\u679c\u8868\u6570\u636e\u91cf\u5f88\u5927\uff0c\u5206\u533a\u53ef\u4ee5\u5c06\u6570\u636e\u5206\u6bb5\u5b58\u50a8\uff0c\u4ece\u800c\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\u3002\u5982\u679c\u5b50\u67e5\u8be2\u6d89\u53ca\u5927\u8868\uff0c\u5c06\u8868\u5206\u533a\u53ef\u4ee5\u63d0\u9ad8\u6027\u80fd\u3002<\/p>\n
7. \u4f18\u5316\u5b50\u67e5\u8be2<\/strong><\/p>\n
\u5982\u679c\u5173\u95ed\u5b50\u67e5\u8be2\u4e0d\u5207\u5b9e\u9645\uff0c\u8fd8\u53ef\u4ee5\u901a\u8fc7\u4f18\u5316\u5b50\u67e5\u8be2\u6765\u63d0\u9ad8\u6027\u80fd\u3002\u4f8b\u5982\uff0c\u4f7f\u7528\u7d22\u5f15\u3001\u5220\u9664\u4e0d\u5fc5\u8981\u7684\u884c\u548c\u5217\uff0c\u4ee5\u53ca\u9650\u5236\u8fd4\u56de\u7ed3\u679c\u7684\u6570\u91cf\u3002<\/p>\n
\u4ee5\u4e0a\u5c31\u662f\u5b50\u67e5\u8be2\u600e\u4e48\u5173\u95ed\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":"
\u5173\u95ed\u5b50\u67e5\u8be2\u53ef\u4ee5\u63d0\u9ad8 oracle \u590d\u6742\u67e5\u8be2\u7684\u6027\u80fd\uff1a\u4f7f\u7528 join \u5c06\u5b50\u67e5\u8be2\u91cd\u5199\u4e3a join\u3002\u5728\u5408\u9002\u7684\u60c5\u51b5\u4e0b\u4f7f\u7528 exists \u8fd0\u7b97\u7b26\u3002\u521b\u5efa\u7269\u5316\u89c6\u56fe\u6765\u5b58\u50a8\u5b50\u67e5\u8be2\u7ed3\u679c\u3002\u4f7f\u7528 common table expressions (cte)\u3002\u4e3a\u8fde\u63a5\u5b57\u6bb5\u5efa\u7acb\u7d22\u5f15\u3002\u5c06\u5927\u8868\u5206\u533a\u4ee5\u63d0\u9ad8\u6548\u7387\u3002\u4f18\u5316\u5b50\u67e5\u8be2\u4ee5\u63d0\u9ad8\u6027\u80fd\u3002 Oracle \u5b50\u67e5\u8be2\u6027\u80fd\u4f18\u5316\uff1a\u5173\u95ed\u5b50\u67e5\u8be2 Oracle \u4e2d\u7684\u5b50\u67e5\u8be2\u53ef\u4ee5\u63d0\u9ad8\u590d\u6742\u67e5\u8be2\u7684\u6548\u7387\uff0c\u4f46\u5982\u679c\u4f7f\u7528\u4e0d\u5f53\uff0c\u4e5f\u4f1a\u5bfc\u81f4\u6027\u80fd\u95ee\u9898\u3002\u5173\u95ed\u5b50\u67e5\u8be2\u53ef\u4ee5\u663e\u8457\u63d0\u9ad8\u6027\u80fd\uff0c\u4e0b\u9762\u4ecb\u7ecd\u5173\u95ed\u5b50\u67e5\u8be2\u7684\u51e0\u79cd\u65b9\u6cd5\uff1a 1. \u4f7f\u7528 JOIN \u5c06\u5b50\u67e5\u8be2\u91cd\u5199\u4e3a JOIN \u53ef\u4ee5\u6d88\u9664\u5b50\u67e5\u8be2\uff0c\u4ece\u800c\u63d0\u9ad8\u6027\u80fd\u3002\u4f8b\u5982\uff1a SELECT * FROM customers WHERE customer_id IN (SELECT customer_id FROM orders); \u767b\u5f55\u540e\u590d\u5236 \u767b\u5f55\u540e\u590d\u5236 \u53ef\u4ee5\u91cd\u5199\u4e3a\uff1a SELECT * FROM customers c JOIN orders o ON c.customer_id = o.customer_id; \u767b\u5f55\u540e\u590d\u5236 2. \u4f7f\u7528 EXISTS \u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u53ef\u4ee5\u4f7f\u7528 EXISTS \u8fd0\u7b97\u7b26\u4ee3\u66ff\u5b50\u67e5\u8be2\u3002\u4f8b\u5982\uff1a […]<\/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-5752","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5752","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=5752"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5752\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=5752"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=5752"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=5752"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}