join.ipynb

{
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     "end_time": "2022-03-14T15:56:37.559514Z",
     "start_time": "2022-03-14T15:56:37.539877Z"
    }
   },
   "outputs": [],
   "source": [
    "import pandas as pd\n",
    "\n",
    "df = pd.DataFrame({'key': ['K0', 'K1', 'K2', 'K3', 'K4', 'K5'],\n",
    "                   'A': ['A0', 'A1', 'A2', 'A3', 'A4', 'A5']})\n",
    "\n",
    "other = pd.DataFrame({'key': ['K0', 'K1', 'K2'],\n",
    "                      'B': ['B0', 'B1', 'B2']})"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {
    "ExecuteTime": {
     "end_time": "2022-03-14T15:57:48.405078Z",
     "start_time": "2022-03-14T15:57:48.372054Z"
    }
   },
   "outputs": [
    {
     "ename": "ValueError",
     "evalue": "You are trying to merge on object and int64 columns. If you wish to proceed you should use pd.concat",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mValueError\u001b[0m                                Traceback (most recent call last)",
      "\u001b[1;32m<ipython-input-12-4cc7ef95f604>\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[1;32m----> 1\u001b[1;33m \u001b[0mdf\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0mjoin\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mother\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mon\u001b[0m\u001b[1;33m=\u001b[0m\u001b[1;34m\"key\"\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[1;32mC:\\ProgramData\\Anaconda3\\lib\\site-packages\\pandas\\core\\frame.py\u001b[0m in \u001b[0;36mjoin\u001b[1;34m(self, other, on, how, lsuffix, rsuffix, sort)\u001b[0m\n\u001b[0;32m   7868\u001b[0m         \u001b[1;36m5\u001b[0m  \u001b[0mK5\u001b[0m  \u001b[0mA5\u001b[0m  \u001b[0mNaN\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m   7869\u001b[0m         \"\"\"\n\u001b[1;32m-> 7870\u001b[1;33m         return self._join_compat(\n\u001b[0m\u001b[0;32m   7871\u001b[0m             \u001b[0mother\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mon\u001b[0m\u001b[1;33m=\u001b[0m\u001b[0mon\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mhow\u001b[0m\u001b[1;33m=\u001b[0m\u001b[0mhow\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mlsuffix\u001b[0m\u001b[1;33m=\u001b[0m\u001b[0mlsuffix\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mrsuffix\u001b[0m\u001b[1;33m=\u001b[0m\u001b[0mrsuffix\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0msort\u001b[0m\u001b[1;33m=\u001b[0m\u001b[0msort\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m   7872\u001b[0m         )\n",
      "\u001b[1;32mC:\\ProgramData\\Anaconda3\\lib\\site-packages\\pandas\\core\\frame.py\u001b[0m in \u001b[0;36m_join_compat\u001b[1;34m(self, other, on, how, lsuffix, rsuffix, sort)\u001b[0m\n\u001b[0;32m   7884\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m   7885\u001b[0m         \u001b[1;32mif\u001b[0m \u001b[0misinstance\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mother\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mDataFrame\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m-> 7886\u001b[1;33m             return merge(\n\u001b[0m\u001b[0;32m   7887\u001b[0m                 \u001b[0mself\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m   7888\u001b[0m                 \u001b[0mother\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;32mC:\\ProgramData\\Anaconda3\\lib\\site-packages\\pandas\\core\\reshape\\merge.py\u001b[0m in \u001b[0;36mmerge\u001b[1;34m(left, right, how, on, left_on, right_on, left_index, right_index, sort, suffixes, copy, indicator, validate)\u001b[0m\n\u001b[0;32m     72\u001b[0m     \u001b[0mvalidate\u001b[0m\u001b[1;33m=\u001b[0m\u001b[1;32mNone\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m     73\u001b[0m ) -> \"DataFrame\":\n\u001b[1;32m---> 74\u001b[1;33m     op = _MergeOperation(\n\u001b[0m\u001b[0;32m     75\u001b[0m         \u001b[0mleft\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m     76\u001b[0m         \u001b[0mright\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;32mC:\\ProgramData\\Anaconda3\\lib\\site-packages\\pandas\\core\\reshape\\merge.py\u001b[0m in \u001b[0;36m__init__\u001b[1;34m(self, left, right, how, on, left_on, right_on, axis, left_index, right_index, sort, suffixes, copy, indicator, validate)\u001b[0m\n\u001b[0;32m    654\u001b[0m         \u001b[1;31m# validate the merge keys dtypes. We may need to coerce\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m    655\u001b[0m         \u001b[1;31m# to avoid incompatible dtypes\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m--> 656\u001b[1;33m         \u001b[0mself\u001b[0m\u001b[1;33m.\u001b[0m\u001b[0m_maybe_coerce_merge_keys\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m    657\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m    658\u001b[0m         \u001b[1;31m# If argument passed to validate,\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;32mC:\\ProgramData\\Anaconda3\\lib\\site-packages\\pandas\\core\\reshape\\merge.py\u001b[0m in \u001b[0;36m_maybe_coerce_merge_keys\u001b[1;34m(self)\u001b[0m\n\u001b[0;32m   1163\u001b[0m                     \u001b[0minferred_right\u001b[0m \u001b[1;32min\u001b[0m \u001b[0mstring_types\u001b[0m \u001b[1;32mand\u001b[0m \u001b[0minferred_left\u001b[0m \u001b[1;32mnot\u001b[0m \u001b[1;32min\u001b[0m \u001b[0mstring_types\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m   1164\u001b[0m                 ):\n\u001b[1;32m-> 1165\u001b[1;33m                     \u001b[1;32mraise\u001b[0m \u001b[0mValueError\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mmsg\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m   1166\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m   1167\u001b[0m             \u001b[1;31m# datetimelikes must match exactly\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mValueError\u001b[0m: You are trying to merge on object and int64 columns. If you wish to proceed you should use pd.concat"
     ]
    }
   ],
   "source": [
    "df.join(other, on=\"key\")"
   ]
  }
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