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Merge 10.5 into 10.6

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Marko Mäkelä
2024-10-03 09:31:39 +03:00
parent cc70ca7eab 170e4555e2
commit 7e0afb1c73
482 changed files with 4427 additions and 623 deletions
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126
mysql-test/main/selectivity_innodb_notembedded.result
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@ -208,6 +208,132 @@ JS
set optimizer_trace=@trace_tmp;
drop table t1;
#
# MDEV-34993: Incorrect cardinality estimation causes poor query plan
#
create table t1 (
pk int,
key1 int,
filler char(100),
index (key1, pk),
primary key (pk)
);
insert into t1
select
seq, FLOOR(seq/100), 'filler'
from
seq_1_to_1000;
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
set optimizer_trace=1;
explain select * from t1
where
pk in (1,2,3,4,5) and
key1 <= 4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,key1 PRIMARY 4 NULL 5 Using where
# Must have a note that "multiplier is too high":
select
json_detailed(json_extract(trace,'$**.selectivity_for_indexes')) as JS
from
information_schema.optimizer_trace;
JS
[
[
{
"index_name": "PRIMARY",
"selectivity_from_index": 0.005
},
{
"index_name": "key1",
"selectivity_from_index": 0.399,
"selectivity_multiplier": 90.9091
}
]
]
# Must not include 1.79...e308 as cost:
select
json_detailed(json_extract(trace,'$**.best_access_path')) as JS
from
information_schema.optimizer_trace;
JS
[
{
"considered_access_paths":
[
{
"access_type": "range",
"resulting_rows": 181.3636545,
"cost": 1.79769e308,
"chosen": true
}
],
"chosen_access_method":
{
"type": "range",
"records": 181.3636545,
"cost": 1.79769e308,
"uses_join_buffering": false
}
}
]
# Disable the fix and try the same:
set @@optimizer_adjust_secondary_key_costs='';
explain select * from t1
where
pk in (1,2,3,4,5) and
key1 <= 4;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,key1 PRIMARY 4 NULL 5 Using where
drop table t1;
# Shows a high multiplier, without a "note":
select
json_detailed(json_extract(trace,'$**.selectivity_for_indexes')) as JS
from
information_schema.optimizer_trace;
JS
[
[
{
"index_name": "PRIMARY",
"selectivity_from_index": 0.005
},
{
"index_name": "key1",
"selectivity_from_index": 0.399,
"selectivity_multiplier": 90.9091
}
]
]
# Includes 1.79...e308 as cost:
select
json_detailed(json_extract(trace,'$**.best_access_path')) as JS
from
information_schema.optimizer_trace;
JS
[
{
"considered_access_paths":
[
{
"access_type": "range",
"resulting_rows": 181.3636545,
"cost": 1.79769e308,
"chosen": true
}
],
"chosen_access_method":
{
"type": "range",
"records": 181.3636545,
"cost": 1.79769e308,
"uses_join_buffering": false
}
}
]
set optimizer_adjust_secondary_key_costs=default;
#
# Clean up
#
set optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;