{"id":5257,"date":"2024-11-14T08:55:35","date_gmt":"2024-11-14T00:55:35","guid":{"rendered":"https:\/\/fwq.ai\/blog\/5257\/"},"modified":"2024-11-14T08:55:35","modified_gmt":"2024-11-14T00:55:35","slug":"mysql-if-else%e8%af%ad%e5%8f%a5%e6%80%8e%e4%b9%88%e5%86%99","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/5257\/","title":{"rendered":"mysql\u00a0if else\u8bed\u53e5\u600e\u4e48\u5199"},"content":{"rendered":"

\n mysql if else \u8bed\u53e5\u53ef\u6839\u636e\u6761\u4ef6\u6267\u884c\u4e0d\u540c\u7684\u4ee3\u7801\u5757\uff0c\u8bed\u6cd5\u4e3a\uff1aif condition then code; else code; end if; \u793a\u4f8b\uff1a\u68c0\u67e5 age \u503c\u662f\u5426\u5927\u4e8e\u7b49\u4e8e 18\uff0c\u5e76\u6839\u636e\u7ed3\u679c\u6253\u5370\u6d88\u606f\u3002\n<\/p><\/blockquote>\n

\"mysql\u00a0if<\/p>\n

MySQL IF ELSE \u8bed\u53e5<\/strong><\/p>\n

\u5982\u4f55\u5199\u5165 IF ELSE \u8bed\u53e5<\/strong><\/p>\n

IF ELSE \u8bed\u53e5\u662f\u4e00\u79cd\u63a7\u5236\u6d41\u8bed\u53e5\uff0c\u7528\u4e8e\u6839\u636e\u6761\u4ef6\u6267\u884c\u4e0d\u540c\u7684\u4ee3\u7801\u5757\u3002\u5b83\u7684\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n

IF condition THEN\n  code_to_execute_if_condition_is_true;\nELSE\n  code_to_execute_if_condition_is_false;\nEND IF;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
IF ELSE \u8bed\u53e5\u793a\u4f8b<\/strong><\/p>\n
\u4e0b\u9762\u7684\u793a\u4f8b\u5c55\u793a\u4e86\u5982\u4f55\u4f7f\u7528 IF ELSE \u8bed\u53e5\u68c0\u67e5\u53d8\u91cf age \u7684\u503c\u5e76\u6839\u636e\u7ed3\u679c\u6253\u5370\u4e0d\u540c\u7684\u6d88\u606f\uff1a<\/p>\n
SET age = 18;\n\nIF age >= 18 THEN\n  PRINT \"\u60a8\u5df2\u7ecf\u6210\u5e74\u3002\";\nELSE\n  PRINT \"\u60a8\u672a\u6210\u5e74\u3002\";\nEND IF;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u7ed3\u679c\uff1a<\/strong><\/p>\n
\u60a8\u5df2\u7ecf\u6210\u5e74\u3002<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u6ce8\u610f\u4e8b\u9879<\/strong><\/p>\n
    \n
  •  \u6761\u4ef6\uff1a<\/strong>\u6761\u4ef6\u53ef\u4ee5\u662f\u4efb\u4f55\u8fd4\u56de\u5e03\u5c14\u503c\u7684\u8868\u8fbe\u5f0f\u3002<\/li>\n
  •  THEN\uff1a<\/strong>\u5982\u679c\u6761\u4ef6\u4e3a true\uff0c\u5219\u6267\u884c THEN \u5757\u4e2d\u7684\u4ee3\u7801\u3002<\/li>\n
  •  ELSE\uff1a<\/strong>\u5982\u679c\u6761\u4ef6\u4e3a false\uff0c\u5219\u6267\u884c ELSE \u5757\u4e2d\u7684\u4ee3\u7801\u3002<\/li>\n
  •  END IF\uff1a<\/strong>\u7ed3\u675f IF ELSE \u8bed\u53e5\u3002<\/li>\n<\/ul>\n
    \u5176\u4ed6\u63a7\u5236\u6d41\u8bed\u53e5<\/strong><\/p>\n
    \u9664\u4e86 IF ELSE \u8bed\u53e5\u4e4b\u5916\uff0cMySQL \u8fd8\u63d0\u4f9b\u5176\u4ed6\u63a7\u5236\u6d41\u8bed\u53e5\uff0c\u5982\uff1a<\/p>\n
      \n
    • CASE WHEN<\/li>\n
    • LOOP<\/li>\n
    • WHILE<\/li>\n
    • REPEAT<\/li>\n<\/ul>\n
      \u4ee5\u4e0a\u5c31\u662f if else\u8bed\u53e5\u600e\u4e48\u5199\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":"
      mysql if else \u8bed\u53e5\u53ef\u6839\u636e\u6761\u4ef6\u6267\u884c\u4e0d\u540c\u7684\u4ee3\u7801\u5757\uff0c\u8bed\u6cd5\u4e3a\uff1aif condition then code; else code; end if; \u793a\u4f8b\uff1a\u68c0\u67e5 age \u503c\u662f\u5426\u5927\u4e8e\u7b49\u4e8e 18\uff0c\u5e76\u6839\u636e\u7ed3\u679c\u6253\u5370\u6d88\u606f\u3002 MySQL IF ELSE \u8bed\u53e5 \u5982\u4f55\u5199\u5165 IF ELSE \u8bed\u53e5 IF ELSE \u8bed\u53e5\u662f\u4e00\u79cd\u63a7\u5236\u6d41\u8bed\u53e5\uff0c\u7528\u4e8e\u6839\u636e\u6761\u4ef6\u6267\u884c\u4e0d\u540c\u7684\u4ee3\u7801\u5757\u3002\u5b83\u7684\u8bed\u6cd5\u5982\u4e0b\uff1a IF condition THEN code_to_execute_if_condition_is_true; ELSE code_to_execute_if_condition_is_false; END IF; \u767b\u5f55\u540e\u590d\u5236 IF ELSE \u8bed\u53e5\u793a\u4f8b \u4e0b\u9762\u7684\u793a\u4f8b\u5c55\u793a\u4e86\u5982\u4f55\u4f7f\u7528 IF ELSE \u8bed\u53e5\u68c0\u67e5\u53d8\u91cf age \u7684\u503c\u5e76\u6839\u636e\u7ed3\u679c\u6253\u5370\u4e0d\u540c\u7684\u6d88\u606f\uff1a SET age = 18; IF age >= 18 THEN PRINT “\u60a8\u5df2\u7ecf\u6210\u5e74\u3002”; […]<\/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-5257","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5257","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=5257"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5257\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=5257"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=5257"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=5257"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}