{"id":294,"date":"2024-12-16T16:27:16","date_gmt":"2024-12-16T08:27:16","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=294"},"modified":"2024-12-16T16:27:16","modified_gmt":"2024-12-16T08:27:16","slug":"oracle%e6%80%8e%e6%a0%b7%e5%a2%9e%e5%8a%a0%e8%a1%a8%e7%9a%84%e5%ad%97%e6%ae%b5%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2024\/12\/16\/oracle%e6%80%8e%e6%a0%b7%e5%a2%9e%e5%8a%a0%e8%a1%a8%e7%9a%84%e5%ad%97%e6%ae%b5%ef%bc%9f\/","title":{"rendered":"oracle\u600e\u6837\u589e\u52a0\u8868\u7684\u5b57\u6bb5\uff1f"},"content":{"rendered":"\n

\u5728Oracle\u6570\u636e\u5e93\u4e2d\uff0c\u589e\u52a0\u8868\u7684\u5b57\u6bb5\uff08\u5373\u6dfb\u52a0\u5217\uff09\u53ef\u4ee5\u4f7f\u7528 ALTER TABLE<\/code> \u8bed\u53e5\u3002\u4e0b\u9762\u662f\u8be6\u7ec6\u7684\u6b65\u9aa4\u548c\u793a\u4f8b\uff1a<\/p>\n\n\n\n

1. \u57fa\u672c\u8bed\u6cd5<\/h3>\n\n\n\n

\u589e\u52a0\u8868\u5b57\u6bb5\u7684\u57fa\u672c\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n\n\n\n

ALTER TABLE table_name ADD column_name data_type [constraints];<\/code><\/pre>\n\n\n\n
    \n
  • table_name<\/code>\uff1a\u9700\u8981\u4fee\u6539\u7684\u8868\u540d\u3002<\/li>\n\n\n\n
  • column_name<\/code>\uff1a\u65b0\u589e\u7684\u5217\u540d\u3002<\/li>\n\n\n\n
  • data_type<\/code>\uff1a\u65b0\u589e\u5217\u7684\u7c7b\u578b\uff0c\u5982 VARCHAR2<\/code>, NUMBER<\/code>, DATE<\/code> \u7b49\u3002<\/li>\n\n\n\n
  • constraints<\/code>\uff08\u53ef\u9009\uff09\uff1a\u5982\u679c\u9700\u8981\uff0c\u53ef\u4ee5\u4e3a\u65b0\u5217\u6307\u5b9a\u7ea6\u675f\u6761\u4ef6\uff0c\u6bd4\u5982 NOT NULL<\/code>, DEFAULT<\/code> \u7b49\u3002<\/li>\n<\/ul>\n\n\n\n
    2. \u793a\u4f8b\uff1a\u589e\u52a0\u5355\u4e2a\u5b57\u6bb5<\/h3>\n\n\n\n
    \u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u540d\u4e3a employees<\/code> \u7684\u8868\uff0c\u6211\u4eec\u8981\u5411\u8be5\u8868\u6dfb\u52a0\u4e00\u4e2a\u540d\u4e3a email<\/code> \u7684\u65b0\u5b57\u6bb5\uff0c\u7c7b\u578b\u4e3a VARCHAR2(100)<\/code>\uff1a<\/p>\n\n\n\n
    ALTER TABLE employees ADD email VARCHAR2(100);<\/code><\/pre>\n\n\n\n
    3. \u793a\u4f8b\uff1a\u589e\u52a0\u591a\u4e2a\u5b57\u6bb5<\/h3>\n\n\n\n
    \u5982\u679c\u9700\u8981\u4e00\u6b21\u6027\u6dfb\u52a0\u591a\u4e2a\u5b57\u6bb5\uff0c\u53ef\u4ee5\u5728 ADD<\/code> \u540e\u5217\u51fa\u591a\u4e2a\u5217\u5b9a\u4e49\uff1a<\/p>\n\n\n\n
    ALTER TABLE employees ADD (\n    phone_number VARCHAR2(15),\n    hire_date DATE,\n    department_id NUMBER\n);<\/code><\/pre>\n\n\n\n
    4. \u4e3a\u5b57\u6bb5\u6dfb\u52a0\u7ea6\u675f<\/h3>\n\n\n\n
    \u5982\u679c\u4f60\u60f3\u5728\u6dfb\u52a0\u5b57\u6bb5\u65f6\u4e3a\u65b0\u5b57\u6bb5\u6307\u5b9a\u7ea6\u675f\uff0c\u53ef\u4ee5\u76f4\u63a5\u5728 ADD<\/code> \u8bed\u53e5\u4e2d\u5b9a\u4e49\u3002\u4f8b\u5982\uff0c\u5982\u679c\u4f60\u5e0c\u671b email<\/code> \u5b57\u6bb5\u4e0d\u80fd\u4e3a NULL<\/code>\uff1a<\/p>\n\n\n\n
    ALTER TABLE employees ADD email VARCHAR2(100) NOT NULL;<\/code><\/pre>\n\n\n\n
    \u6216\u8005\uff0c\u4e3a\u65b0\u5b57\u6bb5\u8bbe\u7f6e\u9ed8\u8ba4\u503c\uff1a<\/p>\n\n\n\n
    ALTER TABLE employees ADD status VARCHAR2(20) DEFAULT 'ACTIVE';<\/code><\/pre>\n\n\n\n
    5. \u6dfb\u52a0\u81ea\u589e\u957f\u5217\uff08Oracle 12c\u53ca\u4ee5\u4e0a\u7248\u672c\uff09<\/h3>\n\n\n\n
    \u5982\u679c\u4f60\u5e0c\u671b\u65b0\u589e\u4e00\u4e2a\u81ea\u589e\u957f\u7684\u5217\uff0cOracle 12c\u53ca\u4ee5\u4e0a\u7248\u672c\u652f\u6301 IDENTITY<\/code> \u5217\u3002\u4ee5\u4e0b\u662f\u793a\u4f8b\uff0c\u65b0\u589e\u4e00\u4e2a id<\/code> \u5b57\u6bb5\uff0c\u5e76\u4f7f\u5176\u81ea\u589e\uff1a<\/p>\n\n\n\n
    ALTER TABLE employees ADD id NUMBER GENERATED ALWAYS AS IDENTITY;<\/code><\/pre>\n\n\n\n
    6. \u67e5\u770b\u8868\u7ed3\u6784<\/h3>\n\n\n\n
    \u589e\u52a0\u5b57\u6bb5\u540e\uff0c\u4f60\u53ef\u4ee5\u4f7f\u7528 DESC<\/code> \u6216 DESCRIBE<\/code> \u547d\u4ee4\u67e5\u770b\u8868\u7684\u7ed3\u6784\uff0c\u786e\u4fdd\u65b0\u5b57\u6bb5\u5df2\u7ecf\u6210\u529f\u6dfb\u52a0\uff1a<\/p>\n\n\n\n
    DESC employees;<\/code><\/pre>\n\n\n\n
    7. \u6ce8\u610f\u4e8b\u9879<\/h3>\n\n\n\n
      \n
    • \u6570\u636e\u7c7b\u578b\u548c\u7ea6\u675f<\/strong>\uff1a\u5728\u6dfb\u52a0\u65b0\u5b57\u6bb5\u65f6\uff0c\u8bf7\u786e\u4fdd\u9009\u62e9\u5408\u9002\u7684\u6570\u636e\u7c7b\u578b\u548c\u7ea6\u675f\u6761\u4ef6\uff0c\u4ee5\u786e\u4fdd\u6570\u636e\u7684\u4e00\u81f4\u6027\u3002<\/li>\n\n\n\n
    • \u9ed8\u8ba4\u503c<\/strong>\uff1a\u5982\u679c\u65b0\u5b57\u6bb5\u5177\u6709\u9ed8\u8ba4\u503c\uff0c\u5219\u5728\u5b57\u6bb5\u6dfb\u52a0\u65f6\uff0c\u6240\u6709\u73b0\u6709\u7684\u884c\u4f1a\u81ea\u52a8\u586b\u5145\u8fd9\u4e2a\u9ed8\u8ba4\u503c\u3002<\/li>\n\n\n\n
    • \u5b57\u6bb5\u987a\u5e8f<\/strong>\uff1aALTER TABLE ADD<\/code> \u8bed\u53e5\u4f1a\u5c06\u65b0\u5b57\u6bb5\u6dfb\u52a0\u5230\u8868\u7684\u6700\u540e\u3002\u5982\u679c\u9700\u8981\u8c03\u6574\u5b57\u6bb5\u7684\u987a\u5e8f\uff0c\u9700\u8981\u4f7f\u7528\u4e00\u4e9b\u66f4\u590d\u6742\u7684\u64cd\u4f5c\uff08\u6bd4\u5982\u521b\u5efa\u4e00\u4e2a\u65b0\u8868\u5e76\u91cd\u65b0\u63d2\u5165\u6570\u636e\uff09\u3002<\/li>\n<\/ul>\n\n\n\n
      8. \u56de\u6eda<\/h3>\n\n\n\n
      \u5982\u679c\u5728\u6dfb\u52a0\u5b57\u6bb5\u540e\u53d1\u73b0\u6709\u95ee\u9898\uff08\u5982\u5b57\u6bb5\u7c7b\u578b\u4e0d\u5bf9\uff0c\u6216\u8005\u5b57\u6bb5\u5185\u5bb9\u9519\u8bef\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528 ALTER TABLE<\/code> \u5220\u9664\u521a\u521a\u6dfb\u52a0\u7684\u5b57\u6bb5\uff1a<\/p>\n\n\n\n
      ALTER TABLE employees DROP COLUMN email;<\/code><\/pre>\n\n\n\n
      \u603b\u7ed3<\/h3>\n\n\n\n
      \u901a\u8fc7 ALTER TABLE ADD<\/code> \u8bed\u53e5\uff0c\u4f60\u53ef\u4ee5\u8f7b\u677e\u5730\u4e3a\u73b0\u6709\u8868\u589e\u52a0\u5b57\u6bb5\uff0c\u5e76\u53ef\u6839\u636e\u9700\u8981\u4e3a\u8fd9\u4e9b\u5b57\u6bb5\u6307\u5b9a\u6570\u636e\u7c7b\u578b\u3001\u7ea6\u675f\u6216\u9ed8\u8ba4\u503c\u7b49\u3002\u66f4\u591a\u8be6\u7ec6\u5185\u5bb9\u8bf7\u5173\u6ce8\u5176\u4ed6\u76f8\u5173\u6587\u7ae0\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
      \u5728Oracle\u6570\u636e\u5e93\u4e2d\uff0c\u589e\u52a0\u8868\u7684\u5b57\u6bb5\uff08\u5373\u6dfb\u52a0\u5217\uff09\u53ef\u4ee5\u4f7f\u7528 ALTER TABLE \u8bed\u53e5\u3002\u4e0b\u9762\u662f\u8be6\u7ec6\u7684\u6b65\u9aa4\u548c\u793a\u4f8b […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[69],"tags":[],"class_list":["post-294","post","type-post","status-publish","format-standard","hentry","category-oracle"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/294","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=294"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/294\/revisions"}],"predecessor-version":[{"id":295,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/294\/revisions\/295"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=294"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=294"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=294"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}