drop table if exists t1,t3;
#
# MDEV-20611: MRR scan over partitioned InnoDB table produces "Out of memory"error
#
create table t1(a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); set @tmp=@@default_storage_engine; set default_storage_engine=InnoDB;
create table t3 (
ID bigint(20) NOT NULL AUTO_INCREMENT,
part_id int,
key_col int,
col2 int,
key(key_col),
PRIMARY KEY (ID,part_id)
) PARTITION BY RANGE (part_id)
(PARTITION p1 VALUES LESS THAN (3),
PARTITION p2 VALUES LESS THAN (7),
PARTITION p3 VALUES LESS THAN (10)
);
show create table t3;
Table Create Table
t3 CREATE TABLE `t3` (
`ID` bigint(20) NOT NULL AUTO_INCREMENT,
`part_id` int(11) NOT NULL,
`key_col` int(11) DEFAULT NULL,
`col2` int(11) DEFAULT NULL,
PRIMARY KEY (`ID`,`part_id`),
KEY `key_col` (`key_col`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
PARTITION BY RANGE (`part_id`)
(PARTITION `p1` VALUES LESS THAN (3) ENGINE = InnoDB,
PARTITION `p2` VALUES LESS THAN (7) ENGINE = InnoDB,
PARTITION `p3` VALUES LESS THAN (10) ENGINE = InnoDB) set default_storage_engine= @tmp;
insert into t3 select
A.a+10*B.a,
A.a,
B.a, 123456
from t1 A, t1 B; set @save_optimizer_switch=@@optimizer_switch; set optimizer_switch='mrr=on';
explain
select * from t3 force index (key_col) where key_col < 3;
id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t3 range key_col key_col 5 NULL # Using index condition; Rowid-ordered scan
select * from t3 force index (key_col) where key_col < 3;
ID part_id key_col col2 100123456 110123456 220123456 1001123456 1111123456 1221123456 2002123456 2112123456 2222123456 330123456 440123456 550123456 660123456 1331123456 1441123456 1551123456 1661123456 2332123456 2442123456 2552123456 2662123456 770123456 880123456 990123456 1771123456 1881123456 1991123456 2772123456 2882123456 2992123456 set optimizer_switch=@save_optimizer_switch;
drop table t1,t3;
#
# MDEV-21544: partitioned table is joined with BKA+MRR
# set @save_join_cache_level=@@join_cache_level; set @save_optimizer_switch=@@optimizer_switch;
create table t0 (
tp int, a int, b int not null, c varchar(12), index idx (a,b)
);
insert into t0 values
(1,3,30,'yyzy'), (1,3,30,'yxxyy'), (1,3,30,'yyxy'), (1,3,30,'xxyy'),
(1,3,30,'yyxz'), (1,3,30,'yyzz'), (1,3,30,'xxyzy'), (1,3,30,'yyyy'),
(1,3,30,'yzzy'), (1,93,30,'zzzy'),
(2,3,40,'yxx'), (2,4,40,'xx'), (2,3,10,'zxz'),
(2,3,40,'yyx'), (2,4,40,'xxx'), (2,3,10,'zyyz'),
(2,3,40,'xzzzz'), (2,4,40,'yyyxx'), (2,3,10,'zyz'),
(2,3,40,'xxx'), (2,4,40,'xx'), (2,3,10,'zzz'),
(2,3,40,'yyxzx'), (2,4,40,'xyx'), (2,3,10,'xzz'),
(2,3,40,'xxxzz'), (2,4,40,'xxz'), (2,3,10,'zzzy'),
(2,3,40,'zzxxx'), (2,4,40,'zxx'), (2,3,10,'yzzz'),
(2,3,40,'xyyxx'), (2,4,40,'xzzzx'), (2,3,10,'zzxxz'),
(2,3,40,'yzxxx'), (2,4,40,'xxzy'), (2,3,10,'zzzyx'),
(2,93,40,'xzx'), (2,94,40,'xz'), (2,93,10,'zyyyz'),
(3,4,30,'yx'), (3,4,30,'yyxxx'), (3,4,30,'zzyy'), (3,4,30,'zxyy'),
(3,4,30,'xxyy'), (3,4,30,'yyzx'), (3,4,30,'zyyy'), (3,4,30,'yzy'),
(3,4,30,'zzzyy'), (3,94,30,'yyz');
create table t1 (
tp int, a int, b int not null, c varchar(12), index idx (a,b)
)
partition by list (tp)
( partition p1 values in (1),
partition p2 values in (2),
partition p3 values in (3));
insert into t1 select * from t0;
create table t2 (a int, index idx(a));
insert into t2 values
(1), (2), (3), (4), (5);
insert into t2 select a+10 from t2;
insert into t2 select a+20 from t2;
analyze table t0,t1,t2;
Table Op Msg_type Msg_text
test.t0 analyze status Engine-independent statistics collected
test.t0 analyze status OK
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status OK set join_cache_level=6; set optimizer_switch='mrr=on';
explain extended select * from t0,t2 where t2.a in (3,4) and t0.a=t2.a and (t0.b / 10) = t2.a-1;
id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 range idx idx 5 NULL 2100.00 Using where; Using index 1 SIMPLE t0 ALL idx NULL NULL NULL 5025.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t0`.`tp` AS `tp`,`test`.`t0`.`a` AS `a`,`test`.`t0`.`b` AS `b`,`test`.`t0`.`c` AS `c`,`test`.`t2`.`a` AS `a` from `test`.`t0` join `test`.`t2` where `test`.`t0`.`a` = `test`.`t2`.`a` and `test`.`t2`.`a` in (3,4) and `test`.`t0`.`b` / 10 = `test`.`t2`.`a` - 1
select * from t0,t2 where t2.a in (3,4) and t0.a=t2.a and (t0.b / 10) = t2.a-1;
tp a b c a 3430 yx 4 3430 yyxxx 4 3430 zzyy 4 3430 zxyy 4 3430 xxyy 4 3430 yyzx 4 3430 zyyy 4 3430 yzy 4 3430 zzzyy 4
explain extended select * from t1,t2 where t2.a in (3,4) and t1.a=t2.a and (t1.b / 10) = t2.a-1;
id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 range idx idx 5 NULL 2100.00 Using where; Using index 1 SIMPLE t1 ref idx idx 5 test.t2.a 12100.00 Using index condition(BKA); Using join buffer (flat, BKA join); Rowid-ordered scan
Warnings:
Note 1003 select `test`.`t1`.`tp` AS `tp`,`test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t1`.`c` AS `c`,`test`.`t2`.`a` AS `a` from `test`.`t1` join `test`.`t2` where `test`.`t1`.`a` = `test`.`t2`.`a` and `test`.`t2`.`a` in (3,4) and `test`.`t1`.`b` / 10 = `test`.`t2`.`a` - 1
select * from t1,t2 where t2.a in (3,4) and t1.a=t2.a and (t1.b / 10) = t2.a-1;
tp a b c a 3430 yx 4 3430 yyxxx 4 3430 zzyy 4 3430 zxyy 4 3430 xxyy 4 3430 yyzx 4 3430 zyyy 4 3430 yzy 4 3430 zzzyy 4
explain extended select * from t0,t2 where t2.a in (3,4) and t0.a=t2.a and (t0.b / 10) = 4;
id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 range idx idx 5 NULL 2100.00 Using where; Using index 1 SIMPLE t0 ALL idx NULL NULL NULL 5025.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t0`.`tp` AS `tp`,`test`.`t0`.`a` AS `a`,`test`.`t0`.`b` AS `b`,`test`.`t0`.`c` AS `c`,`test`.`t2`.`a` AS `a` from `test`.`t0` join `test`.`t2` where `test`.`t0`.`a` = `test`.`t2`.`a` and `test`.`t2`.`a` in (3,4) and `test`.`t0`.`b` / 10 = 4
select * from t0,t2 where t2.a in (3,4) and t0.a=t2.a and (t0.b / 10) = 4;
tp a b c a 2340 yxx 3 2440 xx 4 2340 yyx 3 2440 xxx 4 2340 xzzzz 3 2440 yyyxx 4 2340 xxx 3 2440 xx 4 2340 yyxzx 3 2440 xyx 4 2340 xxxzz 3 2440 xxz 4 2340 zzxxx 3 2440 zxx 4 2340 xyyxx 3 2440 xzzzx 4 2340 yzxxx 3 2440 xxzy 4
explain extended select * from t1,t2 where t2.a in (3,4) and t1.a=t2.a and (t1.b / 10) = 4;
id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 range idx idx 5 NULL 2100.00 Using where; Using index 1 SIMPLE t1 ref idx idx 5 test.t2.a 12100.00 Using index condition; Using join buffer (flat, BKA join); Rowid-ordered scan
Warnings:
Note 1003 select `test`.`t1`.`tp` AS `tp`,`test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t1`.`c` AS `c`,`test`.`t2`.`a` AS `a` from `test`.`t1` join `test`.`t2` where `test`.`t1`.`a` = `test`.`t2`.`a` and `test`.`t2`.`a` in (3,4) and `test`.`t1`.`b` / 10 = 4
select * from t1,t2 where t2.a in (3,4) and t1.a=t2.a and (t1.b / 10) = 4;
tp a b c a 2340 yxx 3 2440 xx 4 2340 yyx 3 2440 xxx 4 2340 xzzzz 3 2440 yyyxx 4 2340 xxx 3 2440 xx 4 2340 yyxzx 3 2440 xyx 4 2340 xxxzz 3 2440 xxz 4 2340 zzxxx 3 2440 zxx 4 2340 xyyxx 3 2440 xzzzx 4 2340 yzxxx 3 2440 xxzy 4
insert into t2 values
(3), (4), (5);
analyze table t2;
Table Op Msg_type Msg_text
test.t2 analyze status Engine-independent statistics collected
test.t2 analyze status OK
explain extended select * from t2 left join t0 on t2.a=t0.a where t2.a in (3,4) and t0.b is null;
id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 range idx idx 5 NULL 4100.00 Using where; Using index 1 SIMPLE t0 ref idx idx 5 test.t2.a 12100.00 Using where; Not exists; Using join buffer (flat, BKA join); Rowid-ordered scan
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t0`.`tp` AS `tp`,`test`.`t0`.`a` AS `a`,`test`.`t0`.`b` AS `b`,`test`.`t0`.`c` AS `c` from `test`.`t2` left join `test`.`t0` on(`test`.`t0`.`a` = `test`.`t2`.`a` and `test`.`t2`.`a` is not null) where `test`.`t2`.`a` in (3,4) and `test`.`t0`.`b` is null
select * from t2 left join t0 on t2.a=t0.a where t2.a in (3,4) and t0.b is null;
a tp a b c
explain extended select * from t2 left join t1 on t2.a=t1.a where t2.a in (3,4) and t1.b is null;
id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE t2 range idx idx 5 NULL 4100.00 Using where; Using index 1 SIMPLE t1 ref idx idx 5 test.t2.a 12100.00 Using where; Not exists; Using join buffer (flat, BKA join); Rowid-ordered scan
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a`,`test`.`t1`.`tp` AS `tp`,`test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b`,`test`.`t1`.`c` AS `c` from `test`.`t2` left join `test`.`t1` on(`test`.`t1`.`a` = `test`.`t2`.`a` and `test`.`t2`.`a` is not null) where `test`.`t2`.`a` in (3,4) and `test`.`t1`.`b` is null
select * from t2 left join t1 on t2.a=t1.a where t2.a in (3,4) and t1.b is null;
a tp a b c set join_cache_level=@save_join_cache_level; set optimizer_switch=@save_optimizer_switch;
drop table t0,t1,t2;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.12 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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