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  1. MariaDB Server
  2. MDEV-21395

Optimizer trace: The object describing table condition selectivity is mis-placed

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      (saw this when looking at MDEV-21377)

      Optimizer trace has rows_estimation node, which includes table. It is followed by
      an unnamed object which has elements name selectivity_for_indexes, selectivity_for_columns , etc. The object itself doesn't have any references to table name which makes it hard to select it using JSONPath.

                  "rows_estimation": [
                    {
                      "table": "o",
                      "range_analysis": { ...
                      }
                    },
                    {
                      "selectivity_for_indexes": [
                        {
                          "index_name": "order_shipment_status",
                          "selectivity_from_index": 0.5
                        },
                        {
                          "index_name": "create_date",
                          "selectivity_from_index": 0.0432
                        }
                      ],
                      "selectivity_for_columns": [],
                      "cond_selectivity": 0.0216
                    },
                    {
                      "table": "op",
                      "range_analysis": {
                        ...
                      }
                    },
                    {
                      "selectivity_for_indexes": [],
                      "selectivity_for_columns": [],
                      "cond_selectivity": 1
                    },
      

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            Assignee:
            psergey Sergei Petrunia
            Reporter:
            psergey Sergei Petrunia
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              Created:
              Updated: