{"id":928660,"date":"2024-12-26T16:39:42","date_gmt":"2024-12-26T08:39:42","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/928660.html"},"modified":"2024-12-26T16:39:44","modified_gmt":"2024-12-26T08:39:44","slug":"python-%e6%b8%b8%e6%a0%87-%e5%a6%82%e4%bd%95%e5%a4%8d%e4%bd%8d","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/928660.html","title":{"rendered":"python \u6e38\u6807 \u5982\u4f55\u590d\u4f4d"},"content":{"rendered":"

\"python<\/p>\n

\u5728Python\u4e2d\uff0c\u6e38\u6807\u590d\u4f4d\u53ef\u4ee5\u901a\u8fc7\u6267\u884c\u6e38\u6807\u7684seek()<\/code>\u65b9\u6cd5\u6216\u8005\u91cd\u65b0\u6267\u884c\u6e38\u6807\u67e5\u8be2\u6765\u5b9e\u73b0\u3001\u8fd9\u4e24\u79cd\u65b9\u6cd5\u5404\u6709\u7279\u70b9\u548c\u9002\u7528\u573a\u666f<\/strong>\u3002\u4f7f\u7528seek()<\/code>\u65b9\u6cd5\u80fd\u591f\u5feb\u901f\u5b9a\u4f4d\u5230\u7ed3\u679c\u96c6\u7684\u5f00\u5934\u6216\u5176\u4ed6\u4f4d\u7f6e\uff0c\u800c\u91cd\u65b0\u6267\u884c\u67e5\u8be2\u5219\u9002\u7528\u4e8e\u52a8\u6001\u6570\u636e\u66f4\u65b0\u7684\u573a\u666f\u3002\u4ee5\u4e0b\u5c06\u8be6\u7ec6\u4ecb\u7ecd\u8fd9\u4e24\u79cd\u65b9\u6cd5\u7684\u4f7f\u7528\u65b9\u6cd5\u548c\u6ce8\u610f\u4e8b\u9879\u3002<\/p>\n<\/p>\n

\u4e00\u3001PYTHON \u6e38\u6807\u7b80\u4ecb<\/p>\n<\/p>\n

\u6e38\u6807\u662f\u6570\u636e\u5e93\u7f16\u7a0b\u4e2d\u5e38\u7528\u7684\u6982\u5ff5\uff0c\u7528\u4e8e\u9010\u884c\u8bfb\u53d6\u67e5\u8be2\u7ed3\u679c\u3002Python\u7684\u6570\u636e\u5e93\u63a5\u53e3\uff08\u5982SQLite\u3001MySQL\u7b49\uff09\u901a\u5e38\u63d0\u4f9b\u6e38\u6807\u5bf9\u8c61\uff0c\u5141\u8bb8\u5f00\u53d1\u8005\u5bf9\u67e5\u8be2\u7ed3\u679c\u8fdb\u884c\u8fed\u4ee3\u5904\u7406\u3002\u6e38\u6807\u5728\u6570\u636e\u5e93\u64cd\u4f5c\u4e2d\u8d77\u5230\u4e86\u975e\u5e38\u91cd\u8981\u7684\u4f5c\u7528\uff0c\u5b83\u80fd\u591f\u8ba9\u7a0b\u5e8f\u9010\u884c\u8bbf\u95ee\u7ed3\u679c\u96c6\uff0c\u7279\u522b\u9002\u7528\u4e8e\u5904\u7406\u5927\u6570\u636e\u91cf\u7684\u573a\u666f\u3002<\/p>\n<\/p>\n

\u6e38\u6807\u7684\u521b\u5efa\u901a\u5e38\u662f\u901a\u8fc7\u8fde\u63a5\u5bf9\u8c61\u7684cursor()<\/code>\u65b9\u6cd5\u5b9e\u73b0\u7684\u3002\u5728\u6267\u884c\u67e5\u8be2\u540e\uff0c\u6e38\u6807\u4f1a\u6307\u5411\u7ed3\u679c\u96c6\u4e2d\u7684\u7b2c\u4e00\u884c\uff0c\u5e76\u53ef\u4ee5\u901a\u8fc7\u8fed\u4ee3\u6216\u6307\u5b9a\u884c\u4f4d\u7f6e\u6765\u8bbf\u95ee\u6570\u636e\u3002\u6e38\u6807\u5bf9\u8c61\u63d0\u4f9b\u4e86\u591a\u79cd\u65b9\u6cd5\u6765\u64cd\u4f5c\u7ed3\u679c\u96c6\uff0c\u5982fetchone()<\/code>\u3001fetchall()<\/code>\u3001fetchmany(size)<\/code>\u7b49\u3002<\/p>\n<\/p>\n

\u4e8c\u3001\u590d\u4f4d\u6e38\u6807\u7684\u65b9\u6cd5<\/p>\n<\/p>\n

    \n
  1. \u901a\u8fc7seek()<\/code>\u590d\u4f4d\u6e38\u6807<\/li>\n<\/ol>\n

    \u4e00\u4e9b\u6570\u636e\u5e93\u63a5\u53e3\u5141\u8bb8\u901a\u8fc7seek()<\/code>\u65b9\u6cd5\u590d\u4f4d\u6e38\u6807\u3002seek()<\/code>\u65b9\u6cd5\u901a\u5e38\u7528\u4e8e\u6587\u4ef6\u64cd\u4f5c\uff0c\u4f46\u5728\u67d0\u4e9b\u6570\u636e\u5e93\u5e93\u4e2d\u4e5f\u53ef\u4ee5\u7528\u4e8e\u6e38\u6807\u64cd\u4f5c\u3002\u7136\u800c\uff0c\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u5e76\u4e0d\u662f\u6240\u6709\u6570\u636e\u5e93\u63a5\u53e3\u90fd\u652f\u6301\u8be5\u65b9\u6cd5\u3002<\/p>\n<\/p>\n

    # \u793a\u4f8b\uff1a\u4f7f\u7528 seek \u65b9\u6cd5\u590d\u4f4d\u6e38\u6807<\/p>\n
    cursor = connection.cursor()<\/p>\n
    cursor.execute("SELECT * FROM your_table")<\/p>\n
    cursor.scroll(0, mode='absolute')  # \u590d\u4f4d\u5230\u7ed3\u679c\u96c6\u7684\u5f00\u59cb<\/p>\n
    <\/code><\/pre>\n<\/p>\n
      \n
    1. \u91cd\u65b0\u6267\u884c\u67e5\u8be2<\/li>\n<\/ol>\n
      \u53e6\u4e00\u79cd\u590d\u4f4d\u6e38\u6807\u7684\u65b9\u6cd5\u662f\u91cd\u65b0\u6267\u884c\u67e5\u8be2\u3002\u8fd9\u79cd\u65b9\u5f0f\u9002\u7528\u4e8e\u5e0c\u671b\u83b7\u53d6\u6700\u65b0\u6570\u636e\u7684\u573a\u666f\uff0c\u56e0\u4e3a\u6bcf\u6b21\u6267\u884c\u67e5\u8be2\u90fd\u4f1a\u4ece\u6570\u636e\u5e93\u83b7\u53d6\u6700\u65b0\u7684\u7ed3\u679c\u96c6\u3002<\/p>\n<\/p>\n
      # \u793a\u4f8b\uff1a\u91cd\u65b0\u6267\u884c\u67e5\u8be2\u590d\u4f4d\u6e38\u6807<\/p>\n
      cursor = connection.cursor()<\/p>\n
      query = "SELECT * FROM your_table"<\/p>\n
      cursor.execute(query)<\/p>\n
      rows = cursor.fetchall()<\/p>\n
      \u91cd\u65b0\u6267\u884c\u540c\u4e00\u67e5\u8be2<\/strong><\/h2>\n
      cursor.execute(query)<\/p>\n
      rows = cursor.fetchall()<\/p>\n
      <\/code><\/pre>\n<\/p>\n
      \u4e09\u3001\u6e38\u6807\u590d\u4f4d\u7684\u6ce8\u610f\u4e8b\u9879<\/p>\n<\/p>\n
        \n
      1. \u6e38\u6807\u72b6\u6001\u7ba1\u7406<\/li>\n<\/ol>\n
        \u5728\u590d\u4f4d\u6e38\u6807\u65f6\uff0c\u9700\u8981\u6ce8\u610f\u6e38\u6807\u7684\u72b6\u6001\u7ba1\u7406\u3002\u67d0\u4e9b\u6570\u636e\u5e93\u5728\u6267\u884c\u67e5\u8be2\u540e\uff0c\u6e38\u6807\u53ef\u80fd\u4f1a\u81ea\u52a8\u5173\u95ed\u3002\u56e0\u6b64\uff0c\u5728\u590d\u4f4d\u6e38\u6807\u4e4b\u524d\uff0c\u786e\u4fdd\u6e38\u6807\u4ecd\u7136\u5904\u4e8e\u6253\u5f00\u72b6\u6001\u3002<\/p>\n<\/p>\n
          \n
        1. \u8d44\u6e90\u7ba1\u7406<\/a><\/li>\n<\/ol>\n
          \u6e38\u6807\u548c\u6570\u636e\u5e93\u8fde\u63a5\u90fd\u662f\u6709\u9650\u7684\u8d44\u6e90\u3002\u5728\u4f7f\u7528\u5b8c\u6e38\u6807\u540e\uff0c\u53ca\u65f6\u5173\u95ed\u6e38\u6807\u548c\u8fde\u63a5\u53ef\u4ee5\u91ca\u653e\u8d44\u6e90\uff0c\u907f\u514d\u7a0b\u5e8f\u4e2d\u51fa\u73b0\u8d44\u6e90\u6cc4\u9732\u95ee\u9898\u3002\u53ef\u4ee5\u4f7f\u7528close()<\/code>\u65b9\u6cd5\u5173\u95ed\u6e38\u6807\u548c\u8fde\u63a5\u3002<\/p>\n<\/p>\n
          # \u5173\u95ed\u6e38\u6807\u548c\u8fde\u63a5<\/p>\n
          cursor.close()<\/p>\n
          connection.close()<\/p>\n
          <\/code><\/pre>\n<\/p>\n
            \n
          1. \u6570\u636e\u4e00\u81f4\u6027<\/li>\n<\/ol>\n
            \u5728\u52a8\u6001\u6570\u636e\u66f4\u65b0\u7684\u573a\u666f\u4e0b\uff0c\u5982\u679c\u901a\u8fc7\u91cd\u65b0\u6267\u884c\u67e5\u8be2\u6765\u590d\u4f4d\u6e38\u6807\uff0c\u53ef\u80fd\u4f1a\u83b7\u53d6\u5230\u4e0e\u521d\u6b21\u67e5\u8be2\u65f6\u4e0d\u540c\u7684\u6570\u636e\u3002\u56e0\u6b64\uff0c\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u9700\u8981\u6839\u636e\u4e1a\u52a1\u903b\u8f91\u5408\u7406\u5904\u7406\u6570\u636e\u4e00\u81f4\u6027\u95ee\u9898\u3002<\/p>\n<\/p>\n
            \u56db\u3001\u6e38\u6807\u590d\u4f4d\u7684\u5b9e\u9645\u5e94\u7528\u573a\u666f<\/p>\n<\/p>\n
              \n
            1. \u5206\u9875\u663e\u793a\u6570\u636e<\/li>\n<\/ol>\n
              \u5728\u6570\u636e\u5206\u9875\u663e\u793a\u7684\u573a\u666f\u4e2d\uff0c\u53ef\u80fd\u9700\u8981\u591a\u6b21\u590d\u4f4d\u6e38\u6807\u4ee5\u5b9e\u73b0\u5206\u9875\u6548\u679c\u3002\u901a\u8fc7\u6e38\u6807\u590d\u4f4d\uff0c\u53ef\u4ee5\u65b9\u4fbf\u5730\u83b7\u53d6\u7279\u5b9a\u9875\u7684\u6570\u636e\uff0c\u5e76\u5728\u7528\u6237\u8bf7\u6c42\u65f6\u52a8\u6001\u52a0\u8f7d\u6570\u636e\u3002<\/p>\n<\/p>\n
                \n
              1. \u52a8\u6001\u5237\u65b0\u6570\u636e<\/li>\n<\/ol>\n
                \u5728\u67d0\u4e9b\u9700\u8981\u52a8\u6001\u5237\u65b0\u6570\u636e\u7684\u5e94\u7528\u4e2d\uff0c\u53ef\u80fd\u9700\u8981\u901a\u8fc7\u91cd\u65b0\u6267\u884c\u67e5\u8be2\u6765\u590d\u4f4d\u6e38\u6807\uff0c\u4ee5\u83b7\u53d6\u6700\u65b0\u7684\u6570\u636e\u3002\u4f8b\u5982\uff0c\u5b9e\u65f6\u76d1\u63a7\u7cfb\u7edf\u4e2d\uff0c\u9700\u8981\u5468\u671f\u6027\u5730\u4ece\u6570\u636e\u5e93\u4e2d\u83b7\u53d6\u6700\u65b0\u7684\u76d1\u63a7\u6570\u636e\u3002<\/p>\n<\/p>\n
                  \n
                1. \u6570\u636e\u7edf\u8ba1\u5206\u6790<\/li>\n<\/ol>\n
                  \u5728\u6570\u636e\u5206\u6790\u8fc7\u7a0b\u4e2d\uff0c\u53ef\u80fd\u9700\u8981\u591a\u6b21\u904d\u5386\u540c\u4e00\u7ed3\u679c\u96c6\u4ee5\u8fdb\u884c\u4e0d\u540c\u7ef4\u5ea6\u7684\u7edf\u8ba1\u5206\u6790\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u53ef\u4ee5\u901a\u8fc7\u590d\u4f4d\u6e38\u6807\u6765\u91cd\u590d\u8bbf\u95ee\u7ed3\u679c\u96c6\u3002<\/p>\n<\/p>\n
                  \u4e94\u3001\u603b\u7ed3<\/p>\n<\/p>\n
                  \u5728Python\u4e2d\uff0c\u6e38\u6807\u590d\u4f4d\u53ef\u4ee5\u901a\u8fc7seek()<\/code>\u65b9\u6cd5\u6216\u91cd\u65b0\u6267\u884c\u67e5\u8be2\u6765\u5b9e\u73b0\u3002\u9009\u62e9\u54ea\u79cd\u65b9\u6cd5\u53d6\u51b3\u4e8e\u5177\u4f53\u7684\u5e94\u7528\u573a\u666f\u548c\u6570\u636e\u5e93\u63a5\u53e3\u7684\u652f\u6301\u60c5\u51b5\u3002\u5728\u4f7f\u7528\u6e38\u6807\u65f6\uff0c\u9700\u8981\u6ce8\u610f\u6e38\u6807\u7684\u72b6\u6001\u7ba1\u7406\u548c\u8d44\u6e90\u7ba1\u7406\uff0c\u786e\u4fdd\u7a0b\u5e8f\u7684\u7a33\u5b9a\u6027\u548c\u6548\u7387\u3002\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u6e38\u6807\u590d\u4f4d\u5e38\u5e38\u7528\u4e8e\u5206\u9875\u663e\u793a\u6570\u636e\u3001\u52a8\u6001\u5237\u65b0\u6570\u636e\u548c\u6570\u636e\u7edf\u8ba1\u5206\u6790\u7b49\u573a\u666f\u3002\u901a\u8fc7\u5408\u7406\u5730\u7ba1\u7406\u6e38\u6807\uff0c\u53ef\u4ee5\u63d0\u9ad8\u7a0b\u5e8f\u7684\u6027\u80fd\u548c\u7528\u6237\u4f53\u9a8c\u3002<\/p>\n<\/p>\n
                  \u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
                   \u5982\u4f55\u5728Python\u4e2d\u590d\u4f4d\u6e38\u6807\u5230\u6587\u4ef6\u7684\u5f00\u5934\uff1f<\/strong>
                  \u5728Python\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528\u6587\u4ef6\u5bf9\u8c61\u7684seek()<\/code>\u65b9\u6cd5\u5c06\u6e38\u6807\u590d\u4f4d\u5230\u6587\u4ef6\u7684\u5f00\u5934\u3002\u5177\u4f53\u6765\u8bf4\uff0c\u60a8\u53ef\u4ee5\u8c03\u7528file.seek(0)<\/code>\uff0c\u5176\u4e2dfile<\/code>\u662f\u60a8\u7684\u6587\u4ef6\u5bf9\u8c61\u3002\u8fd9\u5c06\u4f7f\u6e38\u6807\u8fd4\u56de\u5230\u6587\u4ef6\u7684\u8d77\u59cb\u4f4d\u7f6e\uff0c\u65b9\u4fbf\u60a8\u91cd\u65b0\u8bfb\u53d6\u6587\u4ef6\u5185\u5bb9\u3002<\/p>\n
                  \u6e38\u6807\u590d\u4f4d\u540e\uff0c\u5982\u4f55\u786e\u4fdd\u6570\u636e\u6b63\u786e\u8bfb\u53d6\uff1f<\/strong>
                  \u5728\u590d\u4f4d\u6e38\u6807\u540e\uff0c\u786e\u4fdd\u6570\u636e\u6b63\u786e\u8bfb\u53d6\u7684\u6700\u4f73\u505a\u6cd5\u662f\u4f7f\u7528read()<\/code>\u6216readline()<\/code>\u7b49\u65b9\u6cd5\u91cd\u65b0\u8bfb\u53d6\u6587\u4ef6\u5185\u5bb9\u3002\u590d\u4f4d\u6e38\u6807\u540e\uff0c\u60a8\u53ef\u4ee5\u7b80\u5355\u5730\u8c03\u7528\u8fd9\u4e9b\u65b9\u6cd5\u6765\u83b7\u53d6\u6587\u4ef6\u7684\u6700\u65b0\u5185\u5bb9\u3002\u5bf9\u4e8e\u5927\u578b\u6587\u4ef6\uff0c\u53ef\u4ee5\u4f7f\u7528read(size)<\/code>\u6765\u9010\u5757\u8bfb\u53d6\u6570\u636e\uff0c\u907f\u514d\u4e00\u6b21\u6027\u52a0\u8f7d\u8fc7\u591a\u5185\u5bb9\u3002<\/p>\n
                  \u6e38\u6807\u590d\u4f4d\u5bf9\u6570\u636e\u5e93\u64cd\u4f5c\u6709\u4ec0\u4e48\u5f71\u54cd\uff1f<\/strong>
                  \u5728\u4f7f\u7528\u6570\u636e\u5e93\u8fde\u63a5\u65f6\uff0c\u6e38\u6807\u590d\u4f4d\u901a\u5e38\u610f\u5473\u7740\u91cd\u65b0\u6267\u884c\u67e5\u8be2\u3002\u5982\u679c\u60a8\u5e0c\u671b\u5728\u76f8\u540c\u7684\u6e38\u6807\u5bf9\u8c61\u4e0a\u6267\u884c\u591a\u6b21\u67e5\u8be2\uff0c\u53ef\u4ee5\u5728\u6bcf\u6b21\u6267\u884c\u524d\u786e\u4fdd\u6e38\u6807\u4f4d\u7f6e\u6b63\u786e\u3002\u5bf9\u4e8e\u4e00\u4e9b\u6570\u636e\u5e93API\uff0c\u53ef\u80fd\u9700\u8981\u8c03\u7528execute()<\/code>\u65b9\u6cd5\u6765\u91cd\u65b0\u52a0\u8f7d\u6570\u636e\uff0c\u5e76\u786e\u4fdd\u5728\u5904\u7406\u7ed3\u679c\u96c6\u65f6\u6e38\u6807\u7684\u72b6\u6001\u662f\u6709\u6548\u7684\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728Python\u4e2d\uff0c\u6e38\u6807\u590d\u4f4d\u53ef\u4ee5\u901a\u8fc7\u6267\u884c\u6e38\u6807\u7684seek()\u65b9\u6cd5\u6216\u8005\u91cd\u65b0\u6267\u884c\u6e38\u6807\u67e5\u8be2\u6765\u5b9e\u73b0\u3001\u8fd9\u4e24\u79cd\u65b9\u6cd5\u5404\u6709\u7279\u70b9\u548c\u9002 […]","protected":false},"author":3,"featured_media":928664,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/928660"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=928660"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/928660\/revisions"}],"predecessor-version":[{"id":928667,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/928660\/revisions\/928667"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/928664"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=928660"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=928660"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=928660"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}