config root man

SET optimizer_trace_max_mem_size=1048576;
SET @@session.optimizer_trace="enabled=on";
#
# BUG#18195373: OPTIMIZER TRACE SHOULD PRINT NAME OF
#               INDEX FOR RANGE ACCESS
CREATE TABLE t1 (a VARCHAR(200), b TEXT, FULLTEXT (a,b));
INSERT INTO t1 VALUES('Testing how', 'full-text search'),
('is printed to the', 'optimizer trace.'),
('We need test coverage','of that too');
SELECT * FROM t1 WHERE MATCH(a,b) AGAINST ("coverage");
a	b
We need test coverage	of that too
SELECT * FROM information_schema.OPTIMIZER_TRACE;
QUERY	TRACE	MISSING_BYTES_BEYOND_MAX_MEM_SIZE	INSUFFICIENT_PRIVILEGES
SELECT * FROM t1 WHERE MATCH(a,b) AGAINST ("coverage")	{
  "steps": [
    {
      "join_preparation": {
        "select#": 1,
        "steps": [
          {
            "expanded_query": "/* select#1 */ select `t1`.`a` AS `a`,`t1`.`b` AS `b` from `t1` where (match `t1`.`a`,`t1`.`b` against ('coverage'))"
          }
        ]
      }
    },
    {
      "join_optimization": {
        "select#": 1,
        "steps": [
          {
            "condition_processing": {
              "condition": "WHERE",
              "original_condition": "(match `t1`.`a`,`t1`.`b` against ('coverage'))",
              "steps": [
                {
                  "transformation": "equality_propagation",
                  "resulting_condition": "(match `t1`.`a`,`t1`.`b` against ('coverage'))"
                },
                {
                  "transformation": "constant_propagation",
                  "resulting_condition": "(match `t1`.`a`,`t1`.`b` against ('coverage'))"
                },
                {
                  "transformation": "trivial_condition_removal",
                  "resulting_condition": "(match `t1`.`a`,`t1`.`b` against ('coverage'))"
                }
              ]
            }
          },
          {
            "substitute_generated_columns": {
            }
          },
          {
            "table_dependencies": [
              {
                "table": "`t1`",
                "row_may_be_null": false,
                "map_bit": 0,
                "depends_on_map_bits": [
                ]
              }
            ]
          },
          {
            "ref_optimizer_key_uses": [
              {
                "table": "`t1`",
                "field": "<fulltext>",
                "equals": "(match `t1`.`a`,`t1`.`b` against ('coverage'))",
                "null_rejecting": false
              }
            ]
          },
          {
            "rows_estimation": [
              {
                "table": "`t1`",
                "table_scan": {
                  "rows": 3,
                  "cost": 2
                }
              }
            ]
          },
          {
            "considered_execution_plans": [
              {
                "plan_prefix": [
                ],
                "table": "`t1`",
                "best_access_path": {
                  "considered_access_paths": [
                    {
                      "access_type": "fulltext",
                      "index": "a",
                      "rows": 1,
                      "cost": 1.2,
                      "chosen": true
                    },
                    {
                      "access_type": "scan",
                      "cost": 2.6,
                      "rows": 3,
                      "chosen": false,
                      "cause": "cost"
                    }
                  ]
                },
                "condition_filtering_pct": 100,
                "rows_for_plan": 1,
                "cost_for_plan": 1.2,
                "chosen": true
              }
            ]
          },
          {
            "attaching_conditions_to_tables": {
              "original_condition": "(match `t1`.`a`,`t1`.`b` against ('coverage'))",
              "attached_conditions_computation": [
              ],
              "attached_conditions_summary": [
                {
                  "table": "`t1`",
                  "attached": "(match `t1`.`a`,`t1`.`b` against ('coverage'))"
                }
              ]
            }
          },
          {
            "refine_plan": [
              {
                "table": "`t1`"
              }
            ]
          }
        ]
      }
    },
    {
      "join_execution": {
        "select#": 1,
        "steps": [
        ]
      }
    }
  ]
}	0	0
DROP TABLE t1;