subq11_sj_duplicate-weedout_exp.sql.json

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "8.05"
    },
    "duplicates_removal": {
      "using_temporary_table": true,
      "nested_loop": [
        {
          "table": {
            "table_name": "a",
            "access_type": "ALL",
            "possible_keys": [
              "dept_no"
            ],
            "rows_examined_per_scan": 24,
            "rows_produced_per_join": 7,
            "filtered": "33.33",
            "cost_info": {
              "read_cost": "1.85",
              "eval_cost": "0.80",
              "prefix_cost": "2.65",
              "data_read_per_join": "255"
            },
            "used_columns": [
              "dept_no",
              "from_date"
            ],
            "attached_condition": "(`employees`.`a`.`from_date` >= DATE'1995-01-01')"
          }
        },
        {
          "table": {
            "table_name": "d",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "dept_no"
            ],
            "key_length": "16",
            "ref": [
              "employees.a.dept_no"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 7,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "2.00",
              "eval_cost": "0.80",
              "prefix_cost": "8.05",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "dept_no",
              "dept_name"
            ]
          }
        }
      ]
    }
  }
}