{
  'execution_time' => '0.011',
  'planning_time' => '0.015',
  'top_node' => {
    'actual_loops' => '1',
    'actual_rows' => '1',
    'actual_time_first' => '0.004',
    'actual_time_last' => '0.005',
    'estimated_row_width' => '4',
    'estimated_rows' => '1',
    'estimated_startup_cost' => '0.29',
    'estimated_total_cost' => '8.31',
    'extra_info' => [
      'Index Cond: (id = 1)',
      'Heap Fetches: 1',
      'Buffers: shared hit=3'
    ],
    'is_analyzed' => 1,
    'scan_on' => {
      'index_name' => 'z_pkey',
      'table_alias' => 'z',
      'table_name' => 'z'
    },
    'type' => 'Index Only Scan'
  }
}