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Merge branch '10.4' into bb-10.4-mdev16188

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This commit is contained in:
Igor Babaev
2019-02-14 22:07:33 -08:00
parent ccce4d3be9 282ba973e7
commit 98d55b1366
387 changed files with 24685 additions and 5426 deletions
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249
mysql-test/main/opt_trace_index_merge.result Normal file
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set @tmp_opt_switch= @@optimizer_switch;
set optimizer_switch='index_merge_sort_intersection=on';
set optimizer_trace='enabled=on';
create table t0 (a int);
insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t1 (a int, b int, c int, filler char(100),
key(a), key(b), key(c));
insert into t1 select
A.a * B.a*10 + C.a*100,
A.a * B.a*10 + C.a*100,
A.a,
'filler'
from t0 A, t0 B, t0 C;
This should use union:
explain select * from t1 where a=1 or b=1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge a,b a,b 5,5 NULL 2 Using union(a,b); Using where
select * from information_schema.OPTIMIZER_TRACE;
QUERY TRACE MISSING_BYTES_BEYOND_MAX_MEM_SIZE INSUFFICIENT_PRIVILEGES
explain select * from t1 where a=1 or b=1 {
"steps": [
{
"join_preparation": {
"select_id": 1,
"steps": [
{
"expanded_query": "select `t1`.`a` AS `a`,`t1`.`b` AS `b`,`t1`.`c` AS `c`,`t1`.`filler` AS `filler` from `t1` where `t1`.`a` = 1 or `t1`.`b` = 1"
}
]
}
},
{
"join_optimization": {
"select_id": 1,
"steps": [
{
"condition_processing": {
"condition": "WHERE",
"original_condition": "t1.a = 1 or t1.b = 1",
"steps": [
{
"transformation": "equality_propagation",
"resulting_condition": "multiple equal(1, t1.a) or multiple equal(1, t1.b)"
},
{
"transformation": "constant_propagation",
"resulting_condition": "multiple equal(1, t1.a) or multiple equal(1, t1.b)"
},
{
"transformation": "trivial_condition_removal",
"resulting_condition": "multiple equal(1, t1.a) or multiple equal(1, t1.b)"
}
]
}
},
{
"table_dependencies": [
{
"table": "t1",
"row_may_be_null": false,
"map_bit": 0,
"depends_on_map_bits": []
}
]
},
{
"ref_optimizer_key_uses": []
},
{
"rows_estimation": [
{
"table": "t1",
"range_analysis": {
"table_scan": {
"rows": 1000,
"cost": 231.69
},
"potential_range_indexes": [
{
"index": "a",
"usable": true,
"key_parts": ["a"]
},
{
"index": "b",
"usable": true,
"key_parts": ["b"]
},
{
"index": "c",
"usable": false,
"cause": "not applicable"
}
],
"setup_range_conditions": [],
"group_index_range": {
"chosen": false,
"cause": "no group by or distinct"
},
"analyzing_range_alternatives": {
"range_scan_alternatives": [],
"analyzing_roworder_intersect": {
"cause": "too few roworder scans"
},
"analyzing_sort_intersect": {},
"analyzing_index_merge_union": [
{
"indexes_to_merge": [
{
"range_scan_alternatives": [
{
"index": "a",
"ranges": ["1 <= a <= 1"],
"rowid_ordered": true,
"using_mrr": false,
"index_only": true,
"rows": 1,
"cost": 1.1773,
"chosen": true
}
],
"index_to_merge": "a",
"cumulated_cost": 1.1773
},
{
"range_scan_alternatives": [
{
"index": "b",
"ranges": ["1 <= b <= 1"],
"rowid_ordered": true,
"using_mrr": false,
"index_only": true,
"rows": 1,
"cost": 1.1773,
"chosen": true
}
],
"index_to_merge": "b",
"cumulated_cost": 2.3547
}
],
"cost_of_reading_ranges": 2.3547,
"use_roworder_union": true,
"cause": "always cheaper than non roworder retrieval",
"analyzing_roworder_scans": [
{
"type": "range_scan",
"index": "a",
"rows": 1,
"ranges": ["1 <= a <= 1"],
"analyzing_roworder_intersect": {
"cause": "too few roworder scans"
}
},
{
"type": "range_scan",
"index": "b",
"rows": 1,
"ranges": ["1 <= b <= 1"],
"analyzing_roworder_intersect": {
"cause": "too few roworder scans"
}
}
],
"index_roworder_union_cost": 4.1484,
"members": 2,
"chosen": true
}
]
},
"chosen_range_access_summary": {
"range_access_plan": {
"type": "index_roworder_union",
"union_of": [
{
"type": "range_scan",
"index": "a",
"rows": 1,
"ranges": ["1 <= a <= 1"]
},
{
"type": "range_scan",
"index": "b",
"rows": 1,
"ranges": ["1 <= b <= 1"]
}
]
},
"rows_for_plan": 2,
"cost_for_plan": 4.1484,
"chosen": true
}
}
},
{
"selectivity_for_indexes": [],
"selectivity_for_columns": []
}
]
},
{
"execution_plan_for_potential_materialization": {
"steps": []
}
},
{
"considered_execution_plans": [
{
"plan_prefix": [],
"table": "t1",
"best_access_path": {
"considered_access_paths": [
{
"access_type": "range",
"resulting_rows": 2,
"cost": 4.1484,
"chosen": true
}
]
}
}
]
},
{
"attaching_conditions_to_tables": {
"original_condition": "t1.a = 1 or t1.b = 1",
"attached_conditions_computation": [],
"attached_conditions_summary": [
{
"table": "t1",
"attached": "t1.a = 1 or t1.b = 1"
}
]
}
}
]
}
},
{
"join_execution": {
"select_id": 1,
"steps": []
}
}
]
} 0 0
drop table t0,t1;
set optimizer_trace="enabled=off";
set @@optimizer_switch= @tmp_opt_switch;