很长时间不写代码动手能力明显下降很多常见的错误还是经常发生,今天吐血了一次。

  简单的坑总是要多跳几次才能甘心。很清晰的记得大学的时候在此坑差点闷死,现在又跳进这个坑了,搞了半天终于知道错在哪里。

String sqlString = "insert into cryptcontent(content,assistentContent) value('asf','asfd')";
DBHelper.insertQuery(sqlString);

  这样操作可以的。因此占位符应该也没问题,前提占位符使用正确。代码如下(错误的):

String sqlString = String.format(
"insert into cryptcontent(content,assistentContent) value(%s,%s)",
assistantEncryptResultString, valueString);
DBHelper.insertQuery(sqlString);

此时怎么调试都报错,然后进行调试,报错如下:
  com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'afsdf' in 'field list'

Debug 调试出现:insert into cryptcontent(content,assistentContent) value(afsdf,asfasfd )

aaarticlea/png;base64,iVBORw0KGgoAAAANSUhEUgAAAmYAAAChCAIAAADiPOT4AAAdRElEQVR4nO2d7W8bx53H98/oi7y59tqmpwNcQWkc0+ciyAF5U6FXOGnk2gWsAAcVkWu/uHMugIyLXLgBjLZnszaQXC04le8kW61zQoO46lVnl2VrWyJsi7IkSnx+lEQ9UaRkSwHytPdiyeXs7OzskFxyueL3i88LabkzO/PbmfnuzC650scff7y7u/v06dOtra1cLre6uto77AEAAABanHQ6nc1m19fXNzc3C4XC9va2tLu7u7Oz8+TJk3w+v7a2trS01DvskSEIgiCohdU77InFYplMZmVlZWNjI5/PFwoFaWdn5+nTp9vb25ubm6urq+l0GpYJQRAEtbh6hz3hcDiVSi0vL6+treVyuXw+LylTzEKhsLGxkc1mk8kkLBOCIAhqcfUOexYWFuLxuDrR3NzclJQpZj6fX19fX1paisfjsEwIgiCoxdU77Jmbm4tGo+l0WplobmxsSE+ePNna2lJWZRcXF2OxGCwTgiAIanH1DntmZmbC4XAymVxcXFxZWVlfX5e2t7eVZ2VXVlYymUw0GoVlQhAEQS2u3mHP9PR0MBhU1maz2eza2pq0vb2t3shMpVLhcLh32CPLqaoJhTwAAABAAxD2JrlQoXqHPX6/f35+Xl2bXVlZkba2tpQbmcvLy8lkMhQKwTIBAAA4grpa5qPfPXpZCvytFPmqlPyatHjqh1lJuZGpfCMzkUgEg0FYJgAAAEdQV8t8XXr4z+/NhkKhRCKR+a/M16RlqVAoKJa5uLgYj8cXFhZgmQAAABxBXS2zW3rwk1szyu3MdDq9tLQkFQoF5XfyMplMLBabn593mmWe75I6B6pIOH6iXWrrG29IIffqsUCTgJNuTrUDhQlDfe2SJEldA2Z7DnRK7SfGK01VyxFNk2iKVANGzc+q/LnU1TJ9F31flh5/RVr4Wyn2VSn1nZ8sSvl8nrTMQCBQJ8v0+/2jo6MXL14eHR31+/3WhYzsCee7pKLM21N9R5mhvnapq+9Eu9JiYJlNyXhfm9R13vZiWEAjTnq5c9kStIEuqb1vqLbyV2OZ/EZSQRMi/KOWhldFWsMkLEvTxlk7jhnlXKtlqk2LOkHnu6RyYYwaQF0tc3Jycnp6WnkCKJlM/lhalPL5/MbGhvINE75lfvFF0nSLkWV6PJ7R0VGPx+P3+9W/q2sxrHArgT7fVXbKob52ZeNQX3t1l3K1MtDFa2pWUF3VbAuIpYe2ou7jVp2dJj8RVhRvoFNzGTrQWbl71V6Mob72Wi4LqrJMs0ZSgZET/lGL/VeR1jAJ29I0ceaNY6Y9SMgy1bHaM9ClXo0p0+LOLtq/GQ2gRsvs7u7mWObffG/C7/cHAoFIJJJMJn/xXEbUMn/961+89dYbn34aU7d8+mnsrbfeGBz8D1PL9Pv9Fy9enpiYkGV5oqSLFy9bNNcs9QT2+bPRMtv6BmCZdTq0BXUf6GqiwjRf2MlU5MWorVEa6KxhgluNZZo2kr1omZo4c8Yx8x5U6cKsbn+65KwGUItldpdkaJnSxJcl/1dKD81+56yYZX72Wfytt9548cUXVNdU/FLZ8tlncb5lXrs2PDIy4vF4ZFn2lDQyMnLt2jAnfON9bRI9WyeWhiSpFFzmLFO3f/uJ8WL3O9+l/Dt+or2csK2vr7O4Y/kMqcnb+vq0iypambdgs2PxK1vajSx/WzsdB5FjUQGhQmo0oFAlIYvR2dVOVL/Y4okdyovkvEOXcmAWprJaEFnxU1FXrPYWhjp9ZNzYzYPeUj7p1EdWFI838DU2SozL4qG+dm0/Kt8KocJIXFurRSX/Zvc4opHo8hwol69zQHjIolJVdOrptFUkYY+iuvFKaHZYCo5BGMn8RYZNvbXTW1gFq9oyu7ViWubEhGaWmckIzzI/+aTskbu7IcpB+Zb503d+NjIycuvWLVmWb5U0MjLy03d+JuAxms5JThF0lllcPtI2RGphh/hUYy2lBYHyojy1zGvQtgThH4tdWbWvqlXQlt/ost2kXvTsQWN4DNfU7qMPo/bamVHOcrbGh+YVRqQW+liJpNJ0clsLQ8S2q9TM1IPqmwdnC6Mt1Vw8Q8tsfJRYM8Vy8Yieog+jiWUaFYnobow8iTG9giGLOe0TO/WatFUkMSyS7syazsiJfbRjjkD+WkrGrx/NdIFiFKw6yySd0sg1a7JMcmbZ2fmPRn5pNMu8cuX90dFRWZZHS7py5X3uLFO5VCEu8ah+W/6XDmLxcoZYEyedT3Mri91b2vrGOYerCv6xmJVlXJFRw4eIZeqPxRkKWRkyKq4fxdRaMO8fayzfcBQ2LIxALRixMktFXq7aXhgtusmKrnnot1DXSZqday4eZ/mu0VFi3s0qJdS6BSuMxpbJLJJuTqOfR1JuJDZkGa6UCpx6Om1lSUSHNYHbxmRwyDDWMGzqLVYXKEbBarFMo3+tsUxqPZbpl0b3Mk+eOj0yMqL+dt/IyMjJU6cF7mUq8xW+hzEviNSLHest04KFWXpcMKtsiFX+ulimrp+YW6ZnvK+tvW+IeCrPKstUnbiKAd10/NUuTthcGPLcGc1aiOah38Lb2ZJYiTwP2YAosWc/ysCqtEPjMJpZJrtI5J6MU8Ma002HLJZlCp967by2wiSillbtLLPWYZNuaXWdZerXaa23TMU1r1278MknbL9kWmYo5Lnzpz+fPHX6ypX3FU6eOn3nT3/mnY/xE320zxmtlBI9oXxnWA19tZZZx4VZ3bFMKusZ6OLP3io5Fn9hlj1qlPfvY0x2levNzq528ljl7yGM97UZLcxqszUqjFAtdLGqyAZsL4xHdyAibvrmwdrSbrSzFcUb72uj5k/ttkSJterIaIHMMGoss7in9lNukdh5agxMeMhiWabgqTfwP9EkgsOaUZzpkUF/L7PyYZMYt8u3oksw7mVaZJkissYyTTEKjd/vv3Zt+OSp09euDYs8K1u+a60aYXnxhHwep3zdQV7I0DfDy4+l6KNvMPMr31rXPP5TDWbHYlSWcWOfMb0rVa2CY2lTkffqDTpJuSRM5y6VX/s17a6uTn22mkPT2RoVRqAW7Gc9TFJpnveztzDlU6ZMDiRJktq7OsmpDNU86C3aeQ+1c+2x0vY+8nuZDT1lxk/Maq7SDMLIGCjIIDMfpSEaieGpIb84SMeHPWQx74BWcOrJ5wErTGJYJA1iTyaXg0M6mUj+WliPTZUPUdcnZpvaMi2mIb8rYdvhnAbj68+su3TNhWXfy6yZmr470ToI3GCznHo3kmY89cJxbnQPYhcMlilG3T1sSP2CLeuJSkDAuo/iAMtsml//Ge9rc0S47KXmX/+pkro2kiY89RXFuZE9yJZf/4FlVgKxUAO/NEJZBdJ2e8dYJgDA6cAyAQAAACHELfNRJYJlAgAA2GvAMgEAAAAhHG+ZAAAAQJMBywQAAACEgGUCAAAAQsAyAQAAACFgmWwGe6QOd6TxaQEAADQtsEw2NlrmYE/xlw/guwAA0FTAMtnYZZlet0tyub2ynJLHjkrS0TH7QwEAAEABlsnGJsuM9LvKNul1u6SeMdtDAQAAQKE1LNP38iE93CSDPVKH2320uETaM1jcHul3lX4wVjWziLujtE1xO3ZaYreiirNJkrGj5WPJqbEe1j4AAADsoUUs86WDu5cukPheOshNMtijul2k31WcNXrdPf0RZQd11VQzL+SkFSLi7oBlAgBAs9IilnnowO6lCztnzijsXrrgO3SAm4RcXPW6XWXbY80pqUd1DNOag1kmAAA0L61hmZP7OnbePLvVeWy789hW57GdN89O7uvgJmHZXqTfpa6m0pNLr9ulGifbMkUXZl2liSzuZQIAQHNhkWX+8dF//+HBtVsT7//urwM377w7/IdfNpdlPvvN3Llz2ePHs8e7s8e7c+fOTT67j5uEZXuEn0XcHerCrHtM3U1xuBpmmaRNauwTAACA7VRjmb+/M3H73tRfHgQmpsMPA4mphXTTW+YzbdnLPyeZfKaNm4Rpe8pUUpIkydVzVJ1ljpW+R1laU63FMsknjPANEwAAaCpaxDK/9A09tpcKAACAo2gNywQAAABqBpYJAAAACAHLBAAAAISAZQIAAABCWGSZJb34NiwTAADA3sTaWeaFFyXp232wTAAAAHsQyxdmf/5tqfMELBMAAMCew+KFWUmSJOnvvg/LBAAAsOfA4z8AAACAEFZb5nsnv7InZpk2vWIaAABA82L5wuzfd+2JWWY9LHOw9GO0xI/HjpXeRF3N4dQM4dAAANAAsDDLxnLL9LpdxM+4qz/g7tK9s1oUr9tVen1YxWkBAABUgVyoULDMmtOy3+pV4RE1L+zEmzUBAKABtIZl+l4+pIebZLBH6nC7S6umxUkh+WauskUR745WPMwgbYmxHoOXS5csUPRl1ETO7DwBAABYSYtY5ksHdy9dIPG9dJCbZLBHdbtIv0sqvS+zR7eOqpntcdKW7ZYxHYz0u5jbjYm4O2CZAADQWFrEMg8d2L10YefMGYXdSxd8hw5wkxi+Jpo1p6QewDF5xfRYj0QuzEbcHdU8v4NZJgAANBqLLDOfz29sbKysrGQymVgsFggEmsoyJ/d17Lx5dqvz2Hbnsa3OYztvnp3c18FNwrK9SL9LXSOlJ5det0s1ThPLJHcgHgUqI7owW/Zd3MsEAIAGUI1lTkxM+P3+QCAQiUSSyWQmk2l6y3z2m7lz57LHj2ePd2ePd+fOnZt8dh83Ccv2CJeKuDvUhVn3mLqb4lsGdluyxoi7o5gPY1FXHMIm2c8TAQAAsJYWscxn2rKXf04y+UwbNwlzpqhMJSVJklw9R1W3Gyt9O7L81RHWLFO3okt+KZN+pEiI8rNI+IYJAAA0gBaxzC99Q4/tpQIAAOAoWsMyAQAAgJqBZQIAAABCwDIBAAAAIWCZAAAAgBCwTAAAAEAIWCYAAAAgBCwTAAAAEEJjmd3d3ZRB6rfsDcuUv/76u4ffHjr89tDXX39XlmW7ywMAAKD5oS2T9Ejq3z1lmYffHpI1sr1IAAAAmhyGZSo2Sf69ty2zlnwGexr8Y3Xk28RI8DOzAABQd+h7md1aNd29zC++SFpSbWVh9uuvv1tbPo2zzOILMmu1zMEe/c/Sln/qtvx+FbxKDAAAdDAe/+H4pc2WOTPzR4/nN59/nqi92g6bZUb6XXxHFLJMr9tF/JS8+iPyLt17s9nvLAMAgBaH/cSskV/aaZlffJH0eH5z/folK1xTtcwaS9UgyxzrMXvJSaULs+z9iXewaF9hDQAAwGFfMvn880R1rul7+RCJsjDLsUy3q7wyqX29JfWWrpJlkm++1LwFU10I1WZo+gZpDcSczyBzSZK07/I0yZ+99FqeZQrMawEAoOVwlGXK1bqm76WDu5cukPheOshLUp6EqW9y9rp79AuYfMukXpxZ4eswyxBzWU3m5QzHeiShWWbJ9RklifS7NNsb/mQTAAA0O06zTFlOffJJ7IMP/vP69Utzc/8nmMR36MDupQs7Z84o7F664Dt0gJuk5HaaWZ3+NdFcy9S9QbrKZ2rICR+ZOemRFS7MUhYbcXdI9FNFuJ0JAAAUTrPM6maZk/s6dt48u9V5bLvz2FbnsZ03z07u6+AnUZYuI+6Oos9F+l2q52mmelzLZNlY5QuzrFmmsWWK5V+eAROPAhkcFAAAgJyqr2VWmjUEQRAE7SXBMiEIgiBISLBMCIIgCBJSxfcyO34lAwAAAI6m7vcyYZkAAAD2BrBMAAAAQAhYJgDy4KacmrK/GACAJgeW6QRuy/Km3WXY08Ay7aU/bk/8veprGep69Kr679Epzbt8B29WnMPgJrtqtedcHfU7rkjORtEwwqhNOscyb8opW2yjfscVztnbwGbdDPV1DPbFyksMEP2/kr2y3O/oGt2UU1ZVoXKOTtXXMqvpvxYFhFE1u0Jdv+MK51zZiTbIFpZp33HFcj461dgppt31dRK2xOq2LMuy97bmX9nplmnfRLOjzpZZZf+16ESwLbMlB1J2NLgw2yTHMj0ewy9VVmOZ6nVx8YLrppxS/o/L/fHilJmcX5NlJa+pi9LFiNzHO6UNonosatquDjfEDuXBSOC4SsnJ632rclYxWjPcq/VldwkyYdxkB29cc2j+pyZLc8Zp7YrV4KZuykJdDjv07N/W5ikAOVx4b2srHhdrOaV8qLNfzHmTPhAZecNomPZffqmoT2VZphontz1TQ6imaqY516kP8o9bv5z50RCB1SaNLNNTknWzzJtyilqguK1plKlNemigG4rRIHtTTum76Kam2uXjMnfWGrmmkMbHPTqlPcG6+FadM1U15hC5N+srQH+cHnC9ulkXVV/Op+XmZ3Bdwkvb+FiZxtC5Z5/Z1AWgFqUHNxnn16jl8M6+rsDkxYppNMQrxS6Vcbg4bZKa0bLv3lnRDSvtg+LHtTBnoWjwYZ0+pmV6tLJsYZYKB9m4mcsXXura2SDi/CUd9lX5puYo5Dmg9+e2XbqT3NZ0pKpz1mSoO8perq9gO9Z1Ks6oJHIniWOZvLSNj5VZDB199r2sqxlT6IkU/46pRZZpGo3yRtOpM7NU3BNh1Cb1pWKMFZZ0wwr7YAXHtS5noWiYoW+TesskndLINau/l1kugbaFMVutptdxLZPT05hPRpAb9VepooOXbk1AljXGX2XOJAaWuWfra1wpo4OqUVJFNyT+p8bNzzxt42Nl9qSDo89+dZZJHlrfNUxaDufscyxTIBpk+2GeEZOEZjezGW2SlcTCe5k19UHuceuSs2A0BGotaJlG/9ZqmepskupR9EKHtifwI177rKu6rs4cnjg7VGMhrJWBvVrf4s0h1mKD4HIoe3+BTwX7knhJ6hcrzsKjo89+1QuzHWqPYE1QRM6XNbNM4UoJlUrY2Mjcap9l1rEPGs8F65dzrbNMsYVZvUFaaZnFOsdpgyzep+XMO7XX115yZ13FlNyKW3RfiqIGHfOubnRcXc7U8nL1OWtTMR8f2Hv1VW426AdNKluvtkvrL7boBX/jTw0bm2Bam2LlZZ39foPjOuXsV/H4D5U5/diXWcvhn32qlykzIc2zVNxokHGgMhcqFef+nHBrVxpGRZZZjz7IP279chaKBp9KHv/hqybL1Izv2lareQiNNa02nJ5TSyX61syc2hNTfqU8Xv0+3ONSOVPP4NSSs2YfZo/aY/VVasR8plG7MuOdKta9n1kk4yPqP6UeeiwqLpTW/ljpc3bu2a/5SybKqWTcXyREtRz+2acK7L1NPz9iGA3T/sstFfWpenTBNkkNoZqpCDfn+vVBk+PWL2d+NMQalb5N2mSZukLX+9vEjsZb7YKVg2BeSIFWweweraNxSv9FH9Rg0CZtsExmA4Jl8miBH8zr163Vg9bBxt8xaAQO6b/og1Q0mG2ycZZJLYMYTp9xzgAAADQlzvnBPAAAAMBWYJkAAACAEA2yTAAAAGBPAMsEAAAAhIBlAgAAAELAMgEAAAAhYJkAAACAELBMAAAAQAhYJgAAACAELBMAAAAQApYJAAAACAHLBAAAAISAZQIAAABCwDIBAAAAIWCZAAAAgBCwTAAAAEAIWCYAAAAgBCwTAAAAEAKWCQAAAAgBywQAAACEgGUCAAAAQsAyAQAAACFgmQAAAIAQsEwAAABACFgmAAAAIAQsEwAAABAClgkAAAAIAcsEAAAAhNBYpsfjoQxSvwWWCQAAoDWhLZP0SOpfWCYAAIBWhmGZik2Sf8MyAQAAAPpepkcr3MsEAAAAFBiP/3D8EpYJAACgZWE/MWvkl7BMAAAALQu+ZAIAAAAIAcsEAAAAhIBlAgAAAELAMgEAAAAh6muZEARBELRHVKlf8izTdeRD1TK/9U+/7h02fOgWqpMeQRAEQWJqzLDMm2UeeG0Ulmmj7G6BEARBjlFjhmWhhVlYpi2yuwVCEAQ5Ro0ZlmGZzSu7WyAEQZBj1JhhmW2ZB3/wkevIh8rC7POHh+fm5jiW2V1SY0rcOrK7BUIQBDlG+iG0Ht5EWmY4HE4kEvS9zGg0yrFM+GX9ZHcLhCAIcoyYo6jlDtU77Ll///7U1NTc3Jximel0Wtrc3FQt8/nDw88ZLMzCL+squ1sgBEGQY2Q0kNboU9RbTdiWSc0ymZYJv6y37G6BEARBjhFnLK3FrSq2zFgsZrQwC9esq+xugRAEQY6R0UBqrU+Z3Mt84fu/VX/9pwGlgUjZ3QIhCIIcI+YoWrVDqZNL/SyT/SWTXC7n6holfzDPKGu4Zp1kdwuEIAhyjPRDqCXrsXrLnJycnJ6enp+fj0ajyWRycXFRKhQKuVxudXU1k8nsP3z9W98bxPcyGy+7WyAEQZBj1JhhuXfY4/P5Hj9+vLCwEIvFUqlU0TI3NzfX1tYWFxfj8fjCwgIss/GyuwVCEAQ5RpaMuvrJpX6W+eDBg5mZmWAwGI/H0+n00tKStLW1pVjm0tJSMpkMBoOwzMbL7hYIQRDkGFky6opY5sOHD2dnZ0OhkPLsz/LysrS1taU8AZTNZlOpVDgchmU2Xna3QAiCIMeoMcNy77BnamqKvJGZzWal7e3tQqGQy+WUn5mNRqOwTAiCIKjF1Tvsefz4cTAYjMVi6XR6eXl5ZWVF2t7eVtdml5eXk8lk77AHAAAAaHHIb2Rms9m1tbWiZebz+fX19Ww2m8lk4vF4KBSan5+fnZ2dnp6empp6+PDhgwcPfD7f5OTk/fv37927d/fu3b9CEARBkMN19+7de/fu3b9/f3Jy0ufzPXjw4NGjR9PT03Nzc6FQSHlWdmlpaWVlZW1tTXry5MnW1lahUMjlcmtra4prJhKJaDQaDocXFhYCgcDc3NzMzMz09LTf71eWkhUThSAIgiBH6+HDh4qv+f3+6enpmZmZQCCwsLAQDofV75YoU8yNjQ3p6dOn6kRTdc3FxcV0Op1IJGKxWCQSCYfDwWBwfn4+EAjMzs7Ozs7OzMw8bqzO/+jqc9+9evjy5OPHj6/9e/lvUz333at1LlqjD2SJ/nj5+nPfvfrcj/7XdE+yXsw6mu5gVfJKS1jLGaHSKv+a1k6Bk0+NpapFtZ9H06qJZCKoesRf3UG/W+0FhpyrmZkZxdcCgcD8/HwwGIxEItFoNB6PK365vLy8urq6vr6ey+WknZ2dJ0+eKA8BKY/Orq2traysLC8vZzKZdDqdTCbj8bjqnaFQKBgMLlilv9x59Y07gvv+6b3fvvrelP5vvr71vWtG240w3YHczfRAzSvj4FN1Uf7VbzSNj2AM+THnbNeXVmR/EXFKaBQBoxwqig+jKP/zETO5SPu36jzqUzG3LDRT/EXyEa8758SJ5wM1j+ZLUv4NBoOhUCgcDkcikVgslkgkkslkOp1W5peqX+bzeWl3d5dyzVwut76+vrq6ms1ml5eXFxcXM5lMKpVKJpOJREKxz2g0GrFE972v/dgruO9froy+dmVG/zdfzx8eqn27slH/0fOHh/iIlNA2cYOvVtm0UuQWflSNwshJy8+cypDaoer46zM0LZtpVkZbqEMYxNn3L4f/8Bvi/0rbf43nkZmQuYVTU3FZFX9OPvqmyAmIfjd+wSoqJGS7otFoLBaLx+OKU6ZSqUwmo0wuKb8sFArSxx9/vLu7+/Rpsv/Y2D8c/f3Bo7cO/uCjM9enf/ivfmW6mR33Hnjtgxe+f/PfxjLpsTsvvDqy/9WR/afuJRKJROLR6Vdu7H/lxv5XPvylL5FIJBK+u0eULe88+uCdG/tfuXHk6vy9qx/uL+5248jV+URRalqCk3cThKiE965+qCYv/v3ROCvnBJ0tAblPgiVqH9N8+LmVpUbmlRv7Xxk//c6N0x+VP1RipX76gWHCG/vfeaTJthSB0x+V/9aGURPn01fvHlE/9d09cvIuGWSySIIVFImP+q/+D2offSbMJNRGZv7888UXefQqmhCnwKZ10VcqkUgkEo9Oa1sF2RcSiQTVEYrnlGoq3DLzz6O+wKZVaJ74GxXPKAmzcYo0S34xoKZVMplUnDKdTpNmqTzvs7Gxofrl9vb2/wP9Zrl9mb4DMgAAAABJRU5ErkJggg==" alt="" />

错误找到:注意后面value中的varchar类型的列的字段值没有单引号。故修正:

String sqlString = String.format(
"insert into cryptcontent(content,assistentContent) value('%s','%s')",
assistantEncryptResultString, valueString);
DBHelper.insertQuery(sqlString);

然后执行成功。

JAVA字符串格式化-String.format()的使用

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