{"id":5197,"date":"2024-11-14T10:52:21","date_gmt":"2024-11-14T02:52:21","guid":{"rendered":"https:\/\/fwq.ai\/blog\/5197\/"},"modified":"2024-11-14T10:52:21","modified_gmt":"2024-11-14T02:52:21","slug":"sql%e4%b8%ad%e5%be%aa%e7%8e%af%e8%af%ad%e5%8f%a5%e7%94%a8%e6%b3%95","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/5197\/","title":{"rendered":"sql\u4e2d\u5faa\u73af\u8bed\u53e5\u7528\u6cd5"},"content":{"rendered":"

\n sql \u4e2d\u5faa\u73af\u8bed\u53e5\u5141\u8bb8\u5728\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u524d\u91cd\u590d\u6267\u884c\u8bed\u53e5\u5757\u3002\u6709\u4e24\u79cd\u5faa\u73af\u8bed\u53e5\uff1awhile \u5faa\u73af\u5728\u6267\u884c\u8bed\u53e5\u5757\u524d\u68c0\u67e5\u6761\u4ef6\uff0c\u800c repeat \u5faa\u73af\u5728\u6267\u884c\u8bed\u53e5\u5757\u540e\u68c0\u67e5\u6761\u4ef6\u3002\u5faa\u73af\u8bed\u53e5\u53ef\u7528\u4e8e\u91cd\u590d\u6027\u4efb\u52a1\uff0c\u4f46\u9700\u8981\u8c28\u614e\u4f7f\u7528\u4ee5\u907f\u514d\u65e0\u9650\u5faa\u73af\u3002\n<\/p><\/blockquote>\n

\"sql\u4e2d\u5faa\u73af\u8bed\u53e5\u7528\u6cd5\u63d2\u56fe\"<\/p>\n

SQL \u4e2d\u5faa\u73af\u8bed\u53e5\u7528\u6cd5<\/strong><\/p>\n

1. \u5faa\u73af\u8bed\u53e5\u7684\u4f5c\u7528<\/strong><\/p>\n

\u5faa\u73af\u8bed\u53e5\u5141\u8bb8\u5728 SQL \u4e2d\u6267\u884c\u4e00\u7ec4\u8bed\u53e5\u591a\u6b21\uff0c\u76f4\u5230\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u4e3a\u6b62\u3002\u5b83\u53ef\u4ee5\u7528\u4e8e\u91cd\u590d\u6027\u7684\u4efb\u52a1\uff0c\u4f8b\u5982\u9010\u884c\u5904\u7406\u6570\u636e\u6216\u751f\u6210\u5e8f\u5217\u3002<\/p>\n

2. \u5faa\u73af\u8bed\u53e5\u7684\u8bed\u6cd5<\/strong><\/p>\n

SQL \u4e2d\u6709\u4e24\u79cd\u5faa\u73af\u8bed\u53e5\uff1aWHILE \u5faa\u73af\u548c REPEAT \u5faa\u73af\u3002<\/p>\n

WHILE \u5faa\u73af<\/strong><\/p>\n

WHILE \u6761\u4ef6 DO\n  \u8bed\u53e5\u5757\nEND WHILE;<\/pre>\n
  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n
REPEAT \u5faa\u73af<\/strong><\/p>\n
REPEAT\n  \u8bed\u53e5\u5757\nUNTIL \u6761\u4ef6;<\/pre>\n
  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n
3. WHILE \u5faa\u73af\u7684\u7528\u6cd5<\/strong><\/p>\n
WHILE \u5faa\u73af\u5148\u68c0\u67e5\u6761\u4ef6\uff0c\u5982\u679c\u4e3a\u771f\uff0c\u5219\u6267\u884c\u8bed\u53e5\u5757\u3002\u5982\u679c\u6761\u4ef6\u4e3a\u5047\uff0c\u5faa\u73af\u7ed3\u675f\u3002<\/p>\n
\u793a\u4f8b\uff1a<\/strong><\/p>\n
DECLARE i INT DEFAULT 1;\n\nWHILE i <= 10 DO\n  -- \u6267\u884c\u8bed\u53e5\u5757\n  SET i = i + 1;\nEND WHILE;<\/pre>\n
  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n
4. REPEAT \u5faa\u73af\u7684\u7528\u6cd5<\/strong><\/p>\n
REPEAT \u5faa\u73af\u5148\u6267\u884c\u8bed\u53e5\u5757\uff0c\u7136\u540e\u68c0\u67e5\u6761\u4ef6\u3002\u5982\u679c\u6761\u4ef6\u4e3a\u771f\uff0c\u5faa\u73af\u7ed3\u675f\u3002\u5982\u679c\u6761\u4ef6\u4e3a\u5047\uff0c\u5faa\u73af\u91cd\u590d\u3002<\/p>\n
\u793a\u4f8b\uff1a<\/strong><\/p>\n
DECLARE i INT DEFAULT 0;\n\nREPEAT\n  -- \u6267\u884c\u8bed\u53e5\u5757\n  SET i = i + 1;\nUNTIL i = 10;<\/pre>\n
  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n
5. \u6ce8\u610f\u8981\u70b9<\/strong><\/p>\n
    \n
  • \u5faa\u73af\u8bed\u53e5\u5fc5\u987b\u4ee5\u5206\u53f7\u7ed3\u5c3e\u3002<\/li>\n
  • \u6761\u4ef6\u5fc5\u987b\u662f\u5e03\u5c14\u8868\u8fbe\u5f0f\uff0c\u7ed3\u679c\u4e3a TRUE \u6216 FALSE\u3002<\/li>\n
  • \u5faa\u73af\u53ef\u4ee5\u5d4c\u5957\uff0c\u5373\u5728\u5faa\u73af\u4f53\u5185\u4f7f\u7528\u53e6\u4e00\u4e2a\u5faa\u73af\u3002<\/li>\n
  • \u4f7f\u7528\u5faa\u73af\u8bed\u53e5\u65f6\u8981\u975e\u5e38\u5c0f\u5fc3\uff0c\u56e0\u4e3a\u5b83\u4eec\u53ef\u80fd\u4f1a\u5bfc\u81f4\u65e0\u9650\u5faa\u73af\u3002<\/li>\n<\/ul>\n
    \u4ee5\u4e0a\u5c31\u662fsql\u4e2d\u5faa\u73af\u8bed\u53e5\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":"
    sql \u4e2d\u5faa\u73af\u8bed\u53e5\u5141\u8bb8\u5728\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u524d\u91cd\u590d\u6267\u884c\u8bed\u53e5\u5757\u3002\u6709\u4e24\u79cd\u5faa\u73af\u8bed\u53e5\uff1awhile \u5faa\u73af\u5728\u6267\u884c\u8bed\u53e5\u5757\u524d\u68c0\u67e5\u6761\u4ef6\uff0c\u800c repeat \u5faa\u73af\u5728\u6267\u884c\u8bed\u53e5\u5757\u540e\u68c0\u67e5\u6761\u4ef6\u3002\u5faa\u73af\u8bed\u53e5\u53ef\u7528\u4e8e\u91cd\u590d\u6027\u4efb\u52a1\uff0c\u4f46\u9700\u8981\u8c28\u614e\u4f7f\u7528\u4ee5\u907f\u514d\u65e0\u9650\u5faa\u73af\u3002 SQL \u4e2d\u5faa\u73af\u8bed\u53e5\u7528\u6cd5 1. \u5faa\u73af\u8bed\u53e5\u7684\u4f5c\u7528 \u5faa\u73af\u8bed\u53e5\u5141\u8bb8\u5728 SQL \u4e2d\u6267\u884c\u4e00\u7ec4\u8bed\u53e5\u591a\u6b21\uff0c\u76f4\u5230\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u4e3a\u6b62\u3002\u5b83\u53ef\u4ee5\u7528\u4e8e\u91cd\u590d\u6027\u7684\u4efb\u52a1\uff0c\u4f8b\u5982\u9010\u884c\u5904\u7406\u6570\u636e\u6216\u751f\u6210\u5e8f\u5217\u3002 2. \u5faa\u73af\u8bed\u53e5\u7684\u8bed\u6cd5 SQL \u4e2d\u6709\u4e24\u79cd\u5faa\u73af\u8bed\u53e5\uff1aWHILE \u5faa\u73af\u548c REPEAT \u5faa\u73af\u3002 WHILE \u5faa\u73af WHILE \u6761\u4ef6 DO \u8bed\u53e5\u5757 END WHILE; \u767b\u5f55\u540e\u590d\u5236 REPEAT \u5faa\u73af REPEAT \u8bed\u53e5\u5757 UNTIL \u6761\u4ef6; \u767b\u5f55\u540e\u590d\u5236 3. WHILE \u5faa\u73af\u7684\u7528\u6cd5 WHILE \u5faa\u73af\u5148\u68c0\u67e5\u6761\u4ef6\uff0c\u5982\u679c\u4e3a\u771f\uff0c\u5219\u6267\u884c\u8bed\u53e5\u5757\u3002\u5982\u679c\u6761\u4ef6\u4e3a\u5047\uff0c\u5faa\u73af\u7ed3\u675f\u3002 \u793a\u4f8b\uff1a DECLARE i INT DEFAULT 1; WHILE i <= 10 DO — \u6267\u884c\u8bed\u53e5\u5757 SET i […]<\/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-5197","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5197","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=5197"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5197\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=5197"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=5197"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=5197"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}