| Current Path : /usr/opt/mysql57/mysql-test/suite/opt_trace/r/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/opt/mysql57/mysql-test/suite/opt_trace/r/charset.result |
set @@session.end_markers_in_json=on;
set @@session.optimizer_trace="enabled=on";
create table t1(a int);
insert into t1 values(1);
set names latin1;
explain extended select '', _latin1'' from t1 limit 1;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 NULL ALL NULL NULL NULL NULL 1 100.00 NULL
Warnings:
Warning 1681 'EXTENDED' is deprecated and will be removed in a future release.
Note 1003 /* select#1 */ select '' AS ``,_latin1'\xC1\xC2\xC3\xC4\xC5' AS `` from `test`.`t1` limit 1
select (@query:=QUERY)+NULL, (@trace:=TRACE)+NULL from information_schema.OPTIMIZER_TRACE;
(@query:=QUERY)+NULL (@trace:=TRACE)+NULL
NULL NULL
select @query, @trace;
@query @trace
explain extended select '', _latin1'' from t1 limit 1 {
"steps": [
{
"join_preparation": {
"select#": 1,
"steps": [
{
"expanded_query": "/* select#1 */ select '' AS ``,_latin1'\\xC1\\xC2\\xC3\\xC4\\xC5' AS `` from `t1` limit 1"
}
] /* steps */
} /* join_preparation */
},
{
"join_optimization": {
"select#": 1,
"steps": [
{
"table_dependencies": [
{
"table": "`t1`",
"row_may_be_null": false,
"map_bit": 0,
"depends_on_map_bits": [
] /* depends_on_map_bits */
}
] /* table_dependencies */
},
{
"rows_estimation": [
{
"table": "`t1`",
"table_scan": {
"rows": 1,
"cost": 1
} /* table_scan */
}
] /* rows_estimation */
},
{
"considered_execution_plans": [
{
"plan_prefix": [
] /* plan_prefix */,
"table": "`t1`",
"best_access_path": {
"considered_access_paths": [
{
"rows_to_scan": 1,
"access_type": "scan",
"resulting_rows": 1,
"cost": 1.2,
"chosen": true
}
] /* considered_access_paths */
} /* best_access_path */,
"condition_filtering_pct": 100,
"rows_for_plan": 1,
"cost_for_plan": 1.2,
"chosen": true
}
] /* considered_execution_plans */
},
{
"attaching_conditions_to_tables": {
"original_condition": null,
"attached_conditions_computation": [
] /* attached_conditions_computation */,
"attached_conditions_summary": [
{
"table": "`t1`",
"attached": null
}
] /* attached_conditions_summary */
} /* attaching_conditions_to_tables */
},
{
"refine_plan": [
{
"table": "`t1`"
}
] /* refine_plan */
}
] /* steps */
} /* join_optimization */
},
{
"join_explain": {
"select#": 1,
"steps": [
] /* steps */
} /* join_explain */
}
] /* steps */
}
set names utf8;
select @query, @trace;
@query @trace
explain extended select 'ÁÂÃÄÅ', _latin1'ÁÂÃÄÅ' from t1 limit 1 {
"steps": [
{
"join_preparation": {
"select#": 1,
"steps": [
{
"expanded_query": "/* select#1 */ select 'ÁÂÃÄÅ' AS `ÁÂÃÄÅ`,_latin1'\\xC1\\xC2\\xC3\\xC4\\xC5' AS `ÁÂÃÄÅ` from `t1` limit 1"
}
] /* steps */
} /* join_preparation */
},
{
"join_optimization": {
"select#": 1,
"steps": [
{
"table_dependencies": [
{
"table": "`t1`",
"row_may_be_null": false,
"map_bit": 0,
"depends_on_map_bits": [
] /* depends_on_map_bits */
}
] /* table_dependencies */
},
{
"rows_estimation": [
{
"table": "`t1`",
"table_scan": {
"rows": 1,
"cost": 1
} /* table_scan */
}
] /* rows_estimation */
},
{
"considered_execution_plans": [
{
"plan_prefix": [
] /* plan_prefix */,
"table": "`t1`",
"best_access_path": {
"considered_access_paths": [
{
"rows_to_scan": 1,
"access_type": "scan",
"resulting_rows": 1,
"cost": 1.2,
"chosen": true
}
] /* considered_access_paths */
} /* best_access_path */,
"condition_filtering_pct": 100,
"rows_for_plan": 1,
"cost_for_plan": 1.2,
"chosen": true
}
] /* considered_execution_plans */
},
{
"attaching_conditions_to_tables": {
"original_condition": null,
"attached_conditions_computation": [
] /* attached_conditions_computation */,
"attached_conditions_summary": [
{
"table": "`t1`",
"attached": null
}
] /* attached_conditions_summary */
} /* attaching_conditions_to_tables */
},
{
"refine_plan": [
{
"table": "`t1`"
}
] /* refine_plan */
}
] /* steps */
} /* join_optimization */
},
{
"join_explain": {
"select#": 1,
"steps": [
] /* steps */
} /* join_explain */
}
] /* steps */
}
set names latin1;
create view v1 as select '' as col from t1 limit 1;
select * from v1 where v1.col = '';
col
select (@query:=QUERY)+NULL, (@trace:=TRACE)+NULL from information_schema.OPTIMIZER_TRACE;
(@query:=QUERY)+NULL (@trace:=TRACE)+NULL
NULL NULL
set names utf8;
select @query, @trace;
@query @trace
select * from v1 where v1.col = 'ÁÂÃÄÅ' {
"steps": [
{
"join_preparation": {
"select#": 1,
"steps": [
{
"join_preparation": {
"select#": 2,
"steps": [
{
"expanded_query": "/* select#2 */ select 'ÁÂÃÄÅ' AS `col` from `t1` limit 1"
}
] /* steps */
} /* join_preparation */
},
{
"view": {
"table": "`v1`",
"select#": 2,
"materialized": true
} /* view */
},
{
"expanded_query": "/* select#1 */ select `v1`.`col` AS `col` from `v1` where (`v1`.`col` = 'ÁÂÃÄÅ')"
}
] /* steps */
} /* join_preparation */
},
{
"join_optimization": {
"select#": 1,
"steps": [
{
"join_optimization": {
"select#": 2,
"steps": [
{
"table_dependencies": [
{
"table": "`t1`",
"row_may_be_null": false,
"map_bit": 0,
"depends_on_map_bits": [
] /* depends_on_map_bits */
}
] /* table_dependencies */
},
{
"rows_estimation": [
{
"table": "`t1`",
"table_scan": {
"rows": 1,
"cost": 1
} /* table_scan */
}
] /* rows_estimation */
},
{
"considered_execution_plans": [
{
"plan_prefix": [
] /* plan_prefix */,
"table": "`t1`",
"best_access_path": {
"considered_access_paths": [
{
"rows_to_scan": 1,
"access_type": "scan",
"resulting_rows": 1,
"cost": 1.2,
"chosen": true
}
] /* considered_access_paths */
} /* best_access_path */,
"condition_filtering_pct": 100,
"rows_for_plan": 1,
"cost_for_plan": 1.2,
"chosen": true
}
] /* considered_execution_plans */
},
{
"attaching_conditions_to_tables": {
"original_condition": null,
"attached_conditions_computation": [
] /* attached_conditions_computation */,
"attached_conditions_summary": [
{
"table": "`t1`",
"attached": null
}
] /* attached_conditions_summary */
} /* attaching_conditions_to_tables */
},
{
"refine_plan": [
{
"table": "`t1`"
}
] /* refine_plan */
}
] /* steps */
} /* join_optimization */
},
{
"creating_tmp_table": {
"tmp_table_info": {
"table": "`v1`",
"row_length": 7,
"key_length": 0,
"unique_constraint": false,
"location": "memory (heap)",
"row_limit_estimate": 149796
} /* tmp_table_info */
} /* creating_tmp_table */
},
{
"join_execution": {
"select#": 2,
"steps": [
] /* steps */
} /* join_execution */
},
{
"condition_processing": {
"condition": "WHERE",
"original_condition": "(`v1`.`col` = 'ÁÂÃÄÅ')",
"steps": [
{
"transformation": "equality_propagation",
"resulting_condition": "multiple equal('ÁÂÃÄÅ', `v1`.`col`)"
},
{
"transformation": "constant_propagation",
"resulting_condition": "multiple equal('ÁÂÃÄÅ', `v1`.`col`)"
},
{
"transformation": "trivial_condition_removal",
"resulting_condition": "multiple equal('ÁÂÃÄÅ', `v1`.`col`)"
}
] /* steps */
} /* condition_processing */
},
{
"substitute_generated_columns": {
} /* substitute_generated_columns */
},
{
"table_dependencies": [
{
"table": "`v1`",
"row_may_be_null": false,
"map_bit": 0,
"depends_on_map_bits": [
] /* depends_on_map_bits */
}
] /* table_dependencies */
},
{
"ref_optimizer_key_uses": [
] /* ref_optimizer_key_uses */
},
{
"rows_estimation": [
{
"table": "`v1`",
"rows": 1,
"cost": 1,
"table_type": "system",
"empty": false
}
] /* rows_estimation */
},
{
"condition_on_constant_tables": "1",
"condition_value": true
},
{
"attaching_conditions_to_tables": {
"original_condition": "1",
"attached_conditions_computation": [
] /* attached_conditions_computation */,
"attached_conditions_summary": [
] /* attached_conditions_summary */
} /* attaching_conditions_to_tables */
},
{
"refine_plan": [
] /* refine_plan */
}
] /* steps */
} /* join_optimization */
},
{
"join_execution": {
"select#": 1,
"steps": [
] /* steps */
} /* join_execution */
}
] /* steps */
}
drop table t1;
drop view v1;
set names latin1;
create table t1(c char(4) primary key);
insert into t1 values ('aaa'), ('');
select * from t1 where c < '';
c
aaa
select (@query:=QUERY)+NULL, (@trace:=TRACE)+NULL from information_schema.OPTIMIZER_TRACE;
(@query:=QUERY)+NULL (@trace:=TRACE)+NULL
NULL NULL
set names utf8;
select @query, @trace;
@query @trace
select * from t1 where c < 'ÁÂÃÄÅ' {
"steps": [
{
"join_preparation": {
"select#": 1,
"steps": [
{
"expanded_query": "/* select#1 */ select `t1`.`c` AS `c` from `t1` where (`t1`.`c` < 'ÁÂÃÄÅ')"
}
] /* steps */
} /* join_preparation */
},
{
"join_optimization": {
"select#": 1,
"steps": [
{
"condition_processing": {
"condition": "WHERE",
"original_condition": "(`t1`.`c` < 'ÁÂÃÄÅ')",
"steps": [
{
"transformation": "equality_propagation",
"resulting_condition": "(`t1`.`c` < 'ÁÂÃÄÅ')"
},
{
"transformation": "constant_propagation",
"resulting_condition": "(`t1`.`c` < 'ÁÂÃÄÅ')"
},
{
"transformation": "trivial_condition_removal",
"resulting_condition": "(`t1`.`c` < 'ÁÂÃÄÅ')"
}
] /* steps */
} /* condition_processing */
},
{
"substitute_generated_columns": {
} /* substitute_generated_columns */
},
{
"table_dependencies": [
{
"table": "`t1`",
"row_may_be_null": false,
"map_bit": 0,
"depends_on_map_bits": [
] /* depends_on_map_bits */
}
] /* table_dependencies */
},
{
"ref_optimizer_key_uses": [
] /* ref_optimizer_key_uses */
},
{
"rows_estimation": [
{
"table": "`t1`",
"range_analysis": {
"table_scan": {
"rows": 2,
"cost": 3.5
} /* table_scan */,
"potential_range_indexes": [
{
"index": "PRIMARY",
"usable": true,
"key_parts": [
"c"
] /* key_parts */
}
] /* potential_range_indexes */,
"best_covering_index_scan": {
"index": "PRIMARY",
"cost": 1.401,
"chosen": true
} /* best_covering_index_scan */,
"setup_range_conditions": [
] /* setup_range_conditions */,
"group_index_range": {
"chosen": false,
"cause": "not_group_by_or_distinct"
} /* group_index_range */,
"analyzing_range_alternatives": {
"range_scan_alternatives": [
{
"index": "PRIMARY",
"ranges": [
"c <= ÁÂÃÄ"
] /* ranges */,
"index_dives_for_eq_ranges": true,
"rowid_ordered": true,
"using_mrr": false,
"index_only": true,
"rows": 2,
"cost": 2.41,
"chosen": false,
"cause": "cost"
}
] /* range_scan_alternatives */,
"analyzing_roworder_intersect": {
"usable": false,
"cause": "too_few_roworder_scans"
} /* analyzing_roworder_intersect */
} /* analyzing_range_alternatives */
} /* range_analysis */
}
] /* rows_estimation */
},
{
"considered_execution_plans": [
{
"plan_prefix": [
] /* plan_prefix */,
"table": "`t1`",
"best_access_path": {
"considered_access_paths": [
{
"rows_to_scan": 2,
"access_type": "scan",
"resulting_rows": 2,
"cost": 1.4,
"chosen": true
}
] /* considered_access_paths */
} /* best_access_path */,
"condition_filtering_pct": 100,
"rows_for_plan": 2,
"cost_for_plan": 1.4,
"chosen": true
}
] /* considered_execution_plans */
},
{
"attaching_conditions_to_tables": {
"original_condition": "(`t1`.`c` < 'ÁÂÃÄÅ')",
"attached_conditions_computation": [
] /* attached_conditions_computation */,
"attached_conditions_summary": [
{
"table": "`t1`",
"attached": "(`t1`.`c` < 'ÁÂÃÄÅ')"
}
] /* attached_conditions_summary */
} /* attaching_conditions_to_tables */
},
{
"refine_plan": [
{
"table": "`t1`"
}
] /* refine_plan */
}
] /* steps */
} /* join_optimization */
},
{
"join_execution": {
"select#": 1,
"steps": [
] /* steps */
} /* join_execution */
}
] /* steps */
}
drop table t1;
create table `t
1 a`(`col
1 a` int, index `index
1 a` (`col
1 a`));
insert into `t
1 a` values(2),(3);
create view `v
1 a` as select * from `t
1 a`;
select `col
1 a` from `v
1 a` where `col
1 a` < 6;
col
1 a
2
3
select query, trace from information_schema.OPTIMIZER_TRACE;
query trace
select `col
1 a` from `v
1 a` where `col
1 a` < 6 {
"steps": [
{
"join_preparation": {
"select#": 1,
"steps": [
{
"join_preparation": {
"select#": 2,
"steps": [
{
"expanded_query": "/* select#2 */ select `t\n1\ta`.`col\n1\ta` AS `col\n1\ta` from `t\n1\ta`"
}
] /* steps */
} /* join_preparation */
},
{
"view": {
"table": "`v\n1\ta`",
"select#": 2,
"merged": true
} /* view */
},
{
"expanded_query": "/* select#1 */ select `t\n1\ta`.`col\n1\ta` AS `col\n1\ta` from (`t\n1\ta`) where (`t\n1\ta`.`col\n1\ta` < 6)"
},
{
"transformations_to_nested_joins": {
"transformations": [
"parenthesis_removal"
] /* transformations */,
"expanded_query": "/* select#1 */ select `t\n1\ta`.`col\n1\ta` AS `col\n1\ta` from `t\n1\ta` where (`t\n1\ta`.`col\n1\ta` < 6)"
} /* transformations_to_nested_joins */
}
] /* steps */
} /* join_preparation */
},
{
"join_optimization": {
"select#": 1,
"steps": [
{
"condition_processing": {
"condition": "WHERE",
"original_condition": "(`t\n1\ta`.`col\n1\ta` < 6)",
"steps": [
{
"transformation": "equality_propagation",
"resulting_condition": "(`t\n1\ta`.`col\n1\ta` < 6)"
},
{
"transformation": "constant_propagation",
"resulting_condition": "(`t\n1\ta`.`col\n1\ta` < 6)"
},
{
"transformation": "trivial_condition_removal",
"resulting_condition": "(`t\n1\ta`.`col\n1\ta` < 6)"
}
] /* steps */
} /* condition_processing */
},
{
"substitute_generated_columns": {
} /* substitute_generated_columns */
},
{
"table_dependencies": [
{
"table": "`t\n1\ta`",
"row_may_be_null": false,
"map_bit": 0,
"depends_on_map_bits": [
] /* depends_on_map_bits */
}
] /* table_dependencies */
},
{
"ref_optimizer_key_uses": [
] /* ref_optimizer_key_uses */
},
{
"rows_estimation": [
{
"table": "`t\n1\ta`",
"range_analysis": {
"table_scan": {
"rows": 2,
"cost": 3.5
} /* table_scan */,
"potential_range_indexes": [
{
"index": "index\n1\ta",
"usable": true,
"key_parts": [
"col\n1\ta"
] /* key_parts */
}
] /* potential_range_indexes */,
"best_covering_index_scan": {
"index": "index\n1\ta",
"cost": 1.4013,
"chosen": true
} /* best_covering_index_scan */,
"setup_range_conditions": [
] /* setup_range_conditions */,
"group_index_range": {
"chosen": false,
"cause": "not_group_by_or_distinct"
} /* group_index_range */,
"analyzing_range_alternatives": {
"range_scan_alternatives": [
{
"index": "index\n1\ta",
"ranges": [
"NULL < col\n1\ta < 6"
] /* ranges */,
"index_dives_for_eq_ranges": true,
"rowid_ordered": false,
"using_mrr": false,
"index_only": true,
"rows": 2,
"cost": 1.4113,
"chosen": false,
"cause": "cost"
}
] /* range_scan_alternatives */,
"analyzing_roworder_intersect": {
"usable": false,
"cause": "too_few_roworder_scans"
} /* analyzing_roworder_intersect */
} /* analyzing_range_alternatives */
} /* range_analysis */
}
] /* rows_estimation */
},
{
"considered_execution_plans": [
{
"plan_prefix": [
] /* plan_prefix */,
"table": "`t\n1\ta`",
"best_access_path": {
"considered_access_paths": [
{
"rows_to_scan": 2,
"access_type": "scan",
"resulting_rows": 2,
"cost": 1.4,
"chosen": true
}
] /* considered_access_paths */
} /* best_access_path */,
"condition_filtering_pct": 100,
"rows_for_plan": 2,
"cost_for_plan": 1.4,
"chosen": true
}
] /* considered_execution_plans */
},
{
"attaching_conditions_to_tables": {
"original_condition": "(`t\n1\ta`.`col\n1\ta` < 6)",
"attached_conditions_computation": [
] /* attached_conditions_computation */,
"attached_conditions_summary": [
{
"table": "`t\n1\ta`",
"attached": "(`t\n1\ta`.`col\n1\ta` < 6)"
}
] /* attached_conditions_summary */
} /* attaching_conditions_to_tables */
},
{
"refine_plan": [
{
"table": "`t\n1\ta`"
}
] /* refine_plan */
}
] /* steps */
} /* join_optimization */
},
{
"join_execution": {
"select#": 1,
"steps": [
] /* steps */
} /* join_execution */
}
] /* steps */
}
drop table `t
1 a`;
drop view `v
1 a`;
set optimizer_trace=default;