{"id":95042,"date":"2024-10-19T21:45:18","date_gmt":"2024-10-19T13:45:18","guid":{"rendered":"https:\/\/server.hk\/cnblog\/95042\/"},"modified":"2024-10-19T21:45:19","modified_gmt":"2024-10-19T13:45:19","slug":"oracle%e5%ad%98%e5%84%b2%e9%81%8e%e7%a8%8b%e4%b8%ad%e7%9a%84select%e8%aa%9e%e5%8f%a5","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/95042\/","title":{"rendered":"Oracle\u5b58\u5132\u904e\u7a0b\u4e2d\u7684SELECT\u8a9e\u53e5"},"content":{"rendered":"

Oracle\u5b58\u5132\u904e\u7a0b\u4e2d\u7684SELECT\u8a9e\u53e5<\/h1>\n

\u5728Oracle\u6578\u64da\u5eab\u4e2d\uff0c\u5b58\u5132\u904e\u7a0b\u662f\u4e00\u7a2e\u91cd\u8981\u7684\u6578\u64da\u8655\u7406\u5de5\u5177\uff0c\u80fd\u5920\u5c01\u88dd\u591a\u500bSQL\u8a9e\u53e5\u4ee5\u5be6\u73fe\u7279\u5b9a\u7684\u696d\u52d9\u908f\u8f2f\u3002SELECT\u8a9e\u53e5\u4f5c\u70ba\u6700\u5e38\u7528\u7684SQL\u8a9e\u53e5\u4e4b\u4e00\uff0c\u7d93\u5e38\u88ab\u7528\u65bc\u5b58\u5132\u904e\u7a0b\u4e2d\u4ee5\u67e5\u8a62\u6578\u64da\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eOracle\u5b58\u5132\u904e\u7a0b\u4e2d\u4f7f\u7528SELECT\u8a9e\u53e5\u7684\u57fa\u672c\u6982\u5ff5\u3001\u8a9e\u6cd5\u53ca\u5176\u61c9\u7528\u793a\u4f8b\u3002<\/p>\n

\u5b58\u5132\u904e\u7a0b\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n

\u5b58\u5132\u904e\u7a0b\u662f\u4e00\u7d44\u9810\u7de8\u8b6f\u7684SQL\u8a9e\u53e5\u548cPL\/SQL\u4ee3\u78bc\uff0c\u5b58\u5132\u5728\u6578\u64da\u5eab\u4e2d\uff0c\u53ef\u4ee5\u901a\u904e\u8abf\u7528\u4f86\u57f7\u884c\u3002\u5b83\u5011\u7684\u4e3b\u8981\u512a\u52e2\u5305\u62ec\u63d0\u9ad8\u6027\u80fd\u3001\u91cd\u7528\u4ee3\u78bc\u548c\u589e\u5f37\u5b89\u5168\u6027\u3002\u5b58\u5132\u904e\u7a0b\u53ef\u4ee5\u63a5\u53d7\u53c3\u6578\uff0c\u4e26\u6839\u64da\u9019\u4e9b\u53c3\u6578\u57f7\u884c\u4e0d\u540c\u7684\u64cd\u4f5c\u3002<\/p>\n

SELECT\u8a9e\u53e5\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n

\u5728Oracle\u4e2d\uff0cSELECT\u8a9e\u53e5\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n

SELECT column1, column2, ...\nFROM table_name\nWHERE condition;<\/code><\/pre>\n
\u5728\u5b58\u5132\u904e\u7a0b\u4e2d\uff0cSELECT\u8a9e\u53e5\u901a\u5e38\u7528\u65bc\u5f9e\u6578\u64da\u8868\u4e2d\u6aa2\u7d22\u6578\u64da\uff0c\u4e26\u53ef\u4ee5\u5c07\u7d50\u679c\u5b58\u5132\u5728\u8b8a\u91cf\u4e2d\u6216\u8fd4\u56de\u7d66\u8abf\u7528\u8005\u3002<\/p>\n
\u5728\u5b58\u5132\u904e\u7a0b\u4e2d\u4f7f\u7528SELECT\u8a9e\u53e5<\/h2>\n
\u5728\u5b58\u5132\u904e\u7a0b\u4e2d\u4f7f\u7528SELECT\u8a9e\u53e5\u6642\uff0c\u901a\u5e38\u6703\u4f7f\u7528INTO\u5b50\u53e5\u5c07\u67e5\u8a62\u7d50\u679c\u5b58\u5132\u5230\u8b8a\u91cf\u4e2d\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u793a\u4f8b\uff1a<\/p>\n
CREATE OR REPLACE PROCEDURE get_employee_name (p_employee_id IN NUMBER, p_employee_name OUT VARCHAR2) AS\nBEGIN\n    SELECT name INTO p_employee_name\n    FROM employees\n    WHERE employee_id = p_employee_id;\nEND;<\/code><\/pre>\n
\u5728\u9019\u500b\u793a\u4f8b\u4e2d\uff0c\u5b58\u5132\u904e\u7a0b`get_employee_name`\u63a5\u53d7\u4e00\u500b\u54e1\u5de5ID\u4f5c\u70ba\u8f38\u5165\u53c3\u6578\uff0c\u4e26\u8fd4\u56de\u8a72\u54e1\u5de5\u7684\u59d3\u540d\u3002\u4f7f\u7528INTO\u5b50\u53e5\u5c07\u67e5\u8a62\u7d50\u679c\u5b58\u5132\u5230`p_employee_name`\u8b8a\u91cf\u4e2d\u3002<\/p>\n
\u8655\u7406\u591a\u884c\u7d50\u679c<\/h2>\n
\u5982\u679c\u67e5\u8a62\u53ef\u80fd\u8fd4\u56de\u591a\u884c\u7d50\u679c\uff0c\u5247\u9700\u8981\u4f7f\u7528\u6e38\u6a19\u4f86\u8655\u7406\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528\u6e38\u6a19\u7684\u793a\u4f8b\uff1a<\/p>\n
CREATE OR REPLACE PROCEDURE get_all_employees IS\n    CURSOR emp_cursor IS\n        SELECT name FROM employees;\n    emp_name employees.name%TYPE;\nBEGIN\n    OPEN emp_cursor;\n    LOOP\n        FETCH emp_cursor INTO emp_name;\n        EXIT WHEN emp_cursor%NOTFOUND;\n        DBMS_OUTPUT.PUT_LINE(emp_name);\n    END LOOP;\n    CLOSE emp_cursor;\nEND;<\/code><\/pre>\n
\u5728\u9019\u500b\u793a\u4f8b\u4e2d\uff0c\u5b58\u5132\u904e\u7a0b`get_all_employees`\u4f7f\u7528\u6e38\u6a19\u4f86\u904d\u6b77\u6240\u6709\u54e1\u5de5\u7684\u59d3\u540d\uff0c\u4e26\u4f7f\u7528`DBMS_OUTPUT.PUT_LINE`\u5c07\u5176\u8f38\u51fa\u3002<\/p>\n
\u932f\u8aa4\u8655\u7406<\/h2>\n
\u5728\u5b58\u5132\u904e\u7a0b\u4e2d\uff0c\u932f\u8aa4\u8655\u7406\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u53ef\u4ee5\u4f7f\u7528EXCEPTION\u584a\u4f86\u6355\u7372\u548c\u8655\u7406\u932f\u8aa4\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n
CREATE OR REPLACE PROCEDURE get_employee_name (p_employee_id IN NUMBER, p_employee_name OUT VARCHAR2) AS\nBEGIN\n    SELECT name INTO p_employee_name\n    FROM employees\n    WHERE employee_id = p_employee_id;\nEXCEPTION\n    WHEN NO_DATA_FOUND THEN\n        p_employee_name := 'No employee found';\n    WHEN OTHERS THEN\n        p_employee_name := 'An error occurred';\nEND;<\/code><\/pre>\n
\u5728\u9019\u500b\u793a\u4f8b\u4e2d\uff0c\u5982\u679c\u67e5\u8a62\u672a\u627e\u5230\u4efb\u4f55\u6578\u64da\uff0c\u5247\u6703\u8fd4\u56de\u4e00\u689d\u63d0\u793a\u4fe1\u606f\uff0c\u800c\u4e0d\u662f\u5f15\u767c\u932f\u8aa4\u3002<\/p>\n
\u7e3d\u7d50<\/h2>\n
Oracle\u5b58\u5132\u904e\u7a0b\u4e2d\u7684SELECT\u8a9e\u53e5\u662f\u4e00\u500b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u80fd\u5920\u6709\u6548\u5730\u67e5\u8a62\u548c\u8655\u7406\u6578\u64da\u3002\u901a\u904e\u4f7f\u7528INTO\u5b50\u53e5\u3001\u6e38\u6a19\u548c\u932f\u8aa4\u8655\u7406\u6a5f\u5236\uff0c\u958b\u767c\u8005\u53ef\u4ee5\u69cb\u5efa\u9748\u6d3b\u4e14\u9ad8\u6548\u7684\u6578\u64da\u8655\u7406\u908f\u8f2f\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u5b58\u53d6\u7684\u61c9\u7528\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\u81f3\u95dc\u91cd\u8981\u3002\u82e5\u60a8\u5c0d\u65bc\u9999\u6e2fVPS<\/a><\/code>\u6216\u9999\u6e2f\u4f3a\u670d\u5668<\/a><\/code>\u6709\u8208\u8da3\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u4fe1\u606f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u63a2\u7d22Oracle\u5b58\u5132\u904e\u7a0b\u4e2d\u7684SELECT\u8a9e\u53e5\uff0c\u4e86\u89e3\u5176\u7528\u6cd5\u3001\u6700\u4f73\u5be6\u8e10\u53ca\u6027\u80fd\u512a\u5316\u6280\u5de7\uff0c\u63d0\u5347\u6578\u64da\u67e5\u8a62\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-95042","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95042","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=95042"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95042\/revisions"}],"predecessor-version":[{"id":95043,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/95042\/revisions\/95043"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=95042"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=95042"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=95042"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}