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#
# Range tests without embedded server.
# The first reason to have them is that embedded server doesn't have
# optimizer trace.
#
--source include/not_embedded.inc
--disable_warnings
drop table if exists t1,t2;
--enable_warnings
--echo #
--echo # MDEV-21958: Query having many NOT-IN clauses running forever
--echo #
create table t2 (
pk int primary key,
key1 int,
col1 int,
key (key1, pk)
);
insert into t2 (pk, key1) values (1,1),(2,2),(3,3),(4,4),(5,5);
set @tmp_21958=@@optimizer_trace;
set optimizer_trace=1;
explain select * from t2 where key1 in (1,2,3) and pk not in (1,2,3);
--echo # This should show only ranges in form "(1) <= (key1) <= (1)"
--echo # ranges over "pk" should not be constructed.
select json_detailed(JSON_EXTRACT(trace, '$**.ranges'))
from information_schema.optimizer_trace;
set optimizer_trace=@tmp_21958;
drop table t2;
--echo #
--echo # MDEV-9750: Quick memory exhaustion with 'extended_keys=on'...
--echo #
create table t1 (
kp1 int,
kp2 int,
kp3 int,
kp4 int,
key key1(kp1, kp2, kp3,kp4)
);
insert into t1 values (1,1,1,1),(2,2,2,2),(3,3,3,3);
analyze table t1;
show variables like 'optimizer_max_sel_arg_weight';
# 20 * 20 * 20 *20 = 400*400 = 160,000 ranges
set @tmp_9750=@@optimizer_trace;
set optimizer_trace=1;
explain select * from t1 where
kp1 in (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20) and
kp2 in (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20) and
kp3 in (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20) and
kp4 in (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20)
;
set @json= (select json_detailed(JSON_EXTRACT(trace, '$**.range_scan_alternatives'))
from information_schema.optimizer_trace);
--echo # This will show 3-component ranges.
--echo # The ranges were produced, but the optimizer has cut away kp4
--echo # to keep the number of ranges at manageable level:
select left(@json, 500);
--echo ## Repeat the above with low max_weight:
set @tmp9750_weight=@@optimizer_max_sel_arg_weight;
set optimizer_max_sel_arg_weight=20;
explain select * from t1 where
kp1 in (1,2,3,4,5,6,7,8,9,10) and
kp2 in (1,2,3,4,5,6,7,8,9,10) and
kp3 in (1,2,3,4,5,6,7,8,9,10) and
kp4 in (1,2,3,4,5,6,7,8,9,10)
;
set @trace= (select trace from information_schema.optimizer_trace);
set @json= json_detailed(json_extract(@trace, '$**.range_scan_alternatives'));
select left(@json, 500);
set @json= json_detailed(json_extract(@trace, '$**.setup_range_conditions'));
select left(@json, 2500);
--echo ## Repeat the above with a bit higher max_weight:
set @tmp9750_weight=@@optimizer_max_sel_arg_weight;
set optimizer_max_sel_arg_weight=120;
explain select * from t1 where
kp1 in (1,2,3,4,5,6,7,8,9,10) and
kp2 in (1,2,3,4,5,6,7,8,9,10) and
kp3 in (1,2,3,4,5,6,7,8,9,10) and
kp4 in (1,2,3,4,5,6,7,8,9,10)
;
set @json= (select json_detailed(JSON_EXTRACT(trace, '$**.range_scan_alternatives'))
from information_schema.optimizer_trace);
select left(@json, 1500);
set optimizer_max_sel_arg_weight= @tmp9750_weight;
set optimizer_trace=@tmp_9750;
drop table t1;
--echo #
--echo # MDEV-24739: Assertion `root->weight >= ...' failed in SEL_ARG::tree_delete
--echo #
SELECT *
FROM mysql.help_relation
WHERE NOT (help_topic_id != 8 AND help_keyword_id != 0 OR help_keyword_id = 2 OR help_topic_id < 1900);
SELECT *
FROM mysql.help_relation ignore index (help_topic_id)
WHERE (help_topic_id = 8 OR help_keyword_id = 0) AND help_keyword_id != 2 AND help_topic_id >= 1900;
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