aws-dynamodb-create-describe-table.ipynb

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    "# AWS DynamoDB Create and Describe Table\n",
    "\n",
    "This is a companion notebook for the new [Data Science Solutions](https://strtupsci.com) book. The code is explained in the book.\n",
    "\n",
    "**IMPORTANT.** The code will only run if you have a local DynamoDB server installed and running on localhost port 8000."
   ]
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     "text": [
      "Checking if table exists\n",
      "Table does not exist\n",
      "Creating table\n",
      "Table CensusTest created\n"
     ]
    }
   ],
   "source": [
    "import boto3\n",
    "\n",
    "resource = boto3.resource(\n",
    "    'dynamodb',\n",
    "    endpoint_url='http://localhost:8000')\n",
    "\n",
    "client = boto3.client(\n",
    "    'dynamodb',\n",
    "    endpoint_url='http://localhost:8000')\n",
    "\n",
    "table_to_create = 'Census'\n",
    "print('Checking if table exists')\n",
    "\n",
    "try:\n",
    "    table_description = client.describe_table(TableName=table_to_create)\n",
    "    print('Table {} already exists'.format(table_to_create))\n",
    "    print('Table description:')\n",
    "    print(table_description)\n",
    "\n",
    "# Exception raised by describe_table if table does not exist\n",
    "except Exception as e:\n",
    "    if 'ResourceNotFoundException' in str(e):\n",
    "        print('Table does not exist')\n",
    "        print('Creating table')\n",
    "        table = resource.create_table(\n",
    "            TableName=table_to_create,\n",
    "            KeySchema=[\n",
    "                {'AttributeName': 'uid', 'KeyType': 'HASH'}\n",
    "            ],\n",
    "            AttributeDefinitions=[\n",
    "                {'AttributeName': 'uid', 'AttributeType': 'N' }\n",
    "            ],\n",
    "            ProvisionedThroughput={\n",
    "                'ReadCapacityUnits': 10,\n",
    "                'WriteCapacityUnits': 10\n",
    "            }\n",
    "        )\n",
    "        \n",
    "        #wait for contirmation that the table exists\n",
    "        table.meta.client.get_waiter(\n",
    "            'table_exists').wait(TableName=table_to_create)\n",
    "        print('Table {} created'.format(table_to_create))\n",
    "    else:\n",
    "        print('Table cannot be created')\n",
    "        raise"
   ]
  }
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