title: Connecting Apache Superset with PostgreSQL
body: <p>Suppose I run my Apache Superset on top of the Docker and I want this to connect with my local postgreSQL server. I used the following URI but I got an error:</p>
  
  <p><code>postgresql+psycopg2://username:password@localhost:5432/mydb</code></p>
  
  <p>The error is:</p>
  
  <pre><code>ERROR: {"error": "Connection failed!\n\nThe error message returned was:\n(psycopg2.OperationalError) could not connect to server: Connection refused\n\tIs the server running on host \"localhost\" (127.0.0.1) and accepting\n\tTCP/IP connections on port 5432?\ncould not connect to server: Cannot assign requested address\n\tIs the server running on host \"localhost\" (::1) and accepting\n\tTCP/IP connections on port 5432?\n\n(Background on this error at: http://sqlalche.me/e/e3q8)", "stacktrace": "Traceback (most recent call last):\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/engine/base.py\", line 2265, in _wrap_pool_connect\n    return fn()\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/pool/base.py\", line 303, in unique_connection\n    return _ConnectionFairy._checkout(self)\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/pool/base.py\", line 760, in _checkout\n    fairy = _ConnectionRecord.checkout(pool)\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/pool/base.py\", line 492, in checkout\n    rec = pool._do_get()\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/pool/impl.py\", line 238, in _do_get\n    return self._create_connection()\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/pool/base.py\", line 308, in _create_connection\n    return _ConnectionRecord(self)\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/pool/base.py\", line 437, in __init__\n    self.__connect(first_connect_check=True)\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/pool/base.py\", line 639, in __connect\n    connection = pool._invoke_creator(self)\n  File \"/usr/local/lib/python3.6/site-packages/sqlalchemy/engine/strategies.py\", line 114, in ...
  </code></pre>
  
  <p>How can I solve it?</p>