{
  "steps": [
    {
      "join_preparation": {
        "select_id": 1,
        "steps": [
          {
            "join_preparation": {
              "select_id": 2,
              "steps": [
                {
                  "expanded_query": "/* select#2 */ select count(0) from t1 where year(t1.a) = 2010"
                }
              ]
            }
          },
          {
            "expanded_query": "/* select#1 */ update t1 set t1.c = 0 where year(t1.a) = 2010 and t1.c < (/* select#2 */ select count(0) from t1 where year(t1.a) = 2010)"
          }
        ]
      }
    },
    {
      "join_optimization": {
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        "steps": [
          {
            "join_optimization": {
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              "steps": [
                {
                  "transformation": "date_conds_into_sargable",
                  "before": "year(t1.a) = 2010",
                  "after": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59')"
                },
                {
                  "condition_processing": {
                    "condition": "WHERE",
                    "original_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59')",
                    "steps": [
                      {
                        "transformation": "equality_propagation",
                        "resulting_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59')"
                      },
                      {
                        "transformation": "constant_propagation",
                        "resulting_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59')"
                      },
                      {
                        "transformation": "trivial_condition_removal",
                        "resulting_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59')"
                      }
                    ]
                  }
                },
                {
                  "ref_optimizer_key_uses": []
                },
                {
                  "rows_estimation": [
                    {
                      "table": "t1",
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                          "cost": 0.0119958
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                            "index": "a",
                            "usable": true,
                            "key_parts": ["a", "pk"]
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                          "cost": 0.007672715,
                          "chosen": true
                        },
                        "setup_range_conditions": [],
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                              "ranges": [
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                              "rowid_ordered": false,
                              "using_mrr": false,
                              "index_only": true,
                              "rows": 2,
                              "cost": 0.00273041,
                              "chosen": true
                            }
                          ],
                          "analyzing_roworder_intersect": {
                            "cause": "too few roworder scans"
                          }
                        },
                        "group_index_range": {
                          "chosen": false,
                          "cause": "no group by or distinct"
                        },
                        "chosen_range_access_summary": {
                          "range_access_plan": {
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                            "ranges": [
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                          "chosen": true
                        }
                      }
                    },
                    {
                      "table": "t1",
                      "rowid_filters": [
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                          "build_cost": 0.001885902,
                          "rows": 2
                        }
                      ]
                    },
                    {
                      "selectivity_for_indexes": [
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                          "index_name": "a",
                          "selectivity_from_index": 0.285714286
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                      ],
                      "selectivity_for_columns": [],
                      "cond_selectivity": 0.285714286
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                  ]
                },
                {
                  "table_dependencies": [
                    {
                      "table": "t1",
                      "row_may_be_null": false,
                      "map_bit": 0,
                      "depends_on_map_bits": []
                    }
                  ]
                },
                {
                  "considered_execution_plans": [
                    {
                      "plan_prefix": "",
                      "get_costs_for_tables": [
                        {
                          "best_access_path": {
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                            "plan_details": {
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                            },
                            "considered_access_paths": [
                              {
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                                "rows_after_filter": 2,
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                            ],
                            "chosen_access_method": {
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                              "rows_out": 2,
                              "cost": 0.00273041,
                              "uses_join_buffering": false
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                          }
                        }
                      ]
                    },
                    {
                      "plan_prefix": "",
                      "table": "t1",
                      "rows_for_plan": 2,
                      "cost_for_plan": 0.00273041
                    }
                  ]
                },
                {
                  "best_join_order": ["t1"],
                  "rows": 2,
                  "cost": 0.00273041
                },
                {
                  "substitute_best_equal": {
                    "condition": "WHERE",
                    "resulting_condition": "t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59'"
                  }
                },
                {
                  "attaching_conditions_to_tables": {
                    "attached_conditions_computation": [],
                    "attached_conditions_summary": [
                      {
                        "table": "t1",
                        "attached_condition": "t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59'"
                      }
                    ]
                  }
                },
                {
                  "make_join_readinfo": []
                },
                {
                  "prepare_sum_aggregators": {
                    "function": "count(0)",
                    "aggregator_type": "simple"
                  }
                }
              ]
            }
          },
          {
            "transformation": "date_conds_into_sargable",
            "before": "year(t1.a) = 2010",
            "after": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59')"
          },
          {
            "condition_processing": {
              "condition": "WHERE",
              "original_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59') and t1.c < (/* select#2 */ select count(0) from t1 where t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59')",
              "steps": [
                {
                  "transformation": "equality_propagation",
                  "resulting_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59') and t1.c < (/* select#2 */ select count(0) from t1 where t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59')"
                },
                {
                  "transformation": "constant_propagation",
                  "resulting_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59') and t1.c < (/* select#2 */ select count(0) from t1 where t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59')"
                },
                {
                  "transformation": "trivial_condition_removal",
                  "resulting_condition": "t1.a between <cache>('2010-01-01 00:00:00') and <cache>('2010-12-31 23:59:59') and t1.c < (/* select#2 */ select count(0) from t1 where t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59')"
                }
              ]
            }
          },
          {
            "ref_optimizer_key_uses": []
          },
          {
            "rows_estimation": [
              {
                "table": "t1",
                "range_analysis": {
                  "table_scan": {
                    "rows": 7,
                    "cost": 0.0119958
                  },
                  "potential_range_indexes": [
                    {
                      "index": "PRIMARY",
                      "usable": false,
                      "cause": "not applicable"
                    },
                    {
                      "index": "a",
                      "usable": true,
                      "key_parts": ["a", "pk"]
                    }
                  ],
                  "setup_range_conditions": [],
                  "analyzing_range_alternatives": {
                    "range_scan_alternatives": [
                      {
                        "index": "a",
                        "ranges": [
                          "(2010-01-01 00:00:00) <= (a) <= (2010-12-31 23:59:59)"
                        ],
                        "rowid_ordered": false,
                        "using_mrr": false,
                        "index_only": false,
                        "rows": 2,
                        "cost": 0.00273041,
                        "chosen": true
                      }
                    ],
                    "analyzing_roworder_intersect": {
                      "cause": "too few roworder scans"
                    }
                  },
                  "group_index_range": {
                    "chosen": false,
                    "cause": "no group by or distinct"
                  },
                  "chosen_range_access_summary": {
                    "range_access_plan": {
                      "type": "range_scan",
                      "index": "a",
                      "rows": 2,
                      "ranges": [
                        "(2010-01-01 00:00:00) <= (a) <= (2010-12-31 23:59:59)"
                      ]
                    },
                    "rows_for_plan": 2,
                    "cost_for_plan": 0.00273041,
                    "chosen": true
                  }
                }
              },
              {
                "table": "t1",
                "rowid_filters": [
                  {
                    "key": "a",
                    "build_cost": 0.001885902,
                    "rows": 2
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                ]
              },
              {
                "selectivity_for_indexes": [
                  {
                    "index_name": "a",
                    "selectivity_from_index": 0.285714286
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                ],
                "selectivity_for_columns": [],
                "cond_selectivity": 0.285714286
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            ]
          },
          {
            "table_dependencies": [
              {
                "table": "t1",
                "row_may_be_null": false,
                "map_bit": 0,
                "depends_on_map_bits": []
              }
            ]
          },
          {
            "considered_execution_plans": [
              {
                "plan_prefix": "",
                "get_costs_for_tables": [
                  {
                    "best_access_path": {
                      "table": "t1",
                      "plan_details": {
                        "record_count": 1
                      },
                      "considered_access_paths": [
                        {
                          "access_type": "range",
                          "range_index": "a",
                          "rows": 2,
                          "rows_after_filter": 2,
                          "rows_out": 2,
                          "cost": 0.00273041,
                          "chosen": true
                        }
                      ],
                      "chosen_access_method": {
                        "type": "range",
                        "index": "a",
                        "rows_read": 2,
                        "rows_out": 2,
                        "cost": 0.00273041,
                        "uses_join_buffering": false
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                    }
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                ]
              },
              {
                "plan_prefix": "",
                "table": "t1",
                "rows_for_plan": 2,
                "cost_for_plan": 0.00273041
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            ]
          },
          {
            "best_join_order": ["t1"],
            "rows": 2,
            "cost": 0.00273041
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          {
            "substitute_best_equal": {
              "condition": "WHERE",
              "resulting_condition": "t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59' and t1.c < (/* select#2 */ select count(0) from t1 where t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59')"
            }
          },
          {
            "attaching_conditions_to_tables": {
              "attached_conditions_computation": [],
              "attached_conditions_summary": [
                {
                  "table": "t1",
                  "attached_condition": "t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59' and t1.c < (/* select#2 */ select count(0) from t1 where t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59')"
                }
              ]
            }
          },
          {
            "make_join_readinfo": [
              {
                "table": "t1",
                "index_condition": "t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59'",
                "row_condition": "t1.c < (/* select#2 */ select count(0) from t1 where t1.a between '2010-01-01 00:00:00' and '2010-12-31 23:59:59')"
              }
            ]
          }
        ]
      }
    }
  ]
}