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drop table if exists t1;
create table t1
(
pk1 int not null,
pk2 int not null,
key1 int not null,
key2 int not null,
pktail1ok int not null,
pktail2ok int not null,
pktail3bad int not null,
pktail4bad int not null,
pktail5bad int not null,
pk2copy int not null,
badkey int not null,
filler1 char (200),
filler2 char (200),
key (key1),
key (key2),
/* keys with tails from CPK members */
key (pktail1ok, pk1),
key (pktail2ok, pk1, pk2),
key (pktail3bad, pk2, pk1),
key (pktail4bad, pk1, pk2copy),
key (pktail5bad, pk1, pk2, pk2copy),
primary key (pk1, pk2)
) engine=innodb;
explain select * from t1 where pk1 = 1 and pk2 < 80 and key1=0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,key1 PRIMARY 8 NULL 9 Using where
select * from t1 where pk1 = 1 and pk2 < 80 and key1=0;
pk1 pk2 key1 key2 pktail1ok pktail2ok pktail3bad pktail4bad pktail5bad pk2copy badkey filler1 filler2
1 10 0 0 0 0 0 0 0 10 0 filler-data-10 filler2
1 11 0 0 0 0 0 0 0 11 0 filler-data-11 filler2
1 12 0 0 0 0 0 0 0 12 0 filler-data-12 filler2
1 13 0 0 0 0 0 0 0 13 0 filler-data-13 filler2
1 14 0 0 0 0 0 0 0 14 0 filler-data-14 filler2
1 15 0 0 0 0 0 0 0 15 0 filler-data-15 filler2
1 16 0 0 0 0 0 0 0 16 0 filler-data-16 filler2
1 17 0 0 0 0 0 0 0 17 0 filler-data-17 filler2
1 18 0 0 0 0 0 0 0 18 0 filler-data-18 filler2
1 19 0 0 0 0 0 0 0 19 0 filler-data-19 filler2
explain select pk1,pk2 from t1 where key1 = 10 and key2=10 and 2*pk1+1 < 2*96+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2 key1,key2 4,4 NULL 1 Using intersect(key1,key2); Using where; Using index
select pk1,pk2 from t1 where key1 = 10 and key2=10 and 2*pk1+1 < 2*96+1;
pk1 pk2
95 50
95 51
95 52
95 53
95 54
95 55
95 56
95 57
95 58
95 59
explain select * from t1 where badkey=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1 key1 4 const 100 Using where
explain select * from t1 where pk1 < 7500 and key1 = 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge PRIMARY,key1 key1,PRIMARY 4,4 NULL 38 Using intersect(key1,PRIMARY); Using where
explain select * from t1 where pktail1ok=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,pktail1ok key1,pktail1ok 4,4 NULL 1 Using intersect(key1,pktail1ok); Using where
explain select * from t1 where pktail2ok=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,pktail2ok key1,pktail2ok 4,4 NULL 1 Using intersect(key1,pktail2ok); Using where
select ' The following is actually a deficiency, it uses sort_union currently:' as 'note:';
note:
The following is actually a deficiency, it uses sort_union currently:
explain select * from t1 where (pktail2ok=1 and pk1< 50000) or key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge PRIMARY,key1,pktail2ok pktail2ok,key1 8,4 NULL 199 Using sort_union(pktail2ok,key1); Using where
explain select * from t1 where pktail3bad=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail3bad key1 4 const 100 Using where
explain select * from t1 where pktail4bad=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail4bad key1 4 const 100 Using where
explain select * from t1 where pktail5bad=1 and key1=10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref key1,pktail5bad key1 4 const 100 Using where
explain select pk1,pk2,key1,key2 from t1 where key1 = 10 and key2=10 limit 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge key1,key2 key1,key2 4,4 NULL 1 Using intersect(key1,key2); Using where; Using index
select pk1,pk2,key1,key2 from t1 where key1 = 10 and key2=10 limit 10;
pk1 pk2 key1 key2
95 50 10 10
95 51 10 10
95 52 10 10
95 53 10 10
95 54 10 10
95 55 10 10
95 56 10 10
95 57 10 10
95 58 10 10
95 59 10 10
drop table t1;
create table t1
(
RUNID varchar(22),
SUBMITNR varchar(5),
ORDERNR char(1) ,
PROGRAMM varchar(8),
TESTID varchar(4),
UCCHECK char(1),
ETEXT varchar(80),
ETEXT_TYPE char(1),
INFO char(1),
SEVERITY tinyint(3),
TADIRFLAG char(1),
PRIMARY KEY (RUNID,SUBMITNR,ORDERNR,PROGRAMM,TESTID,UCCHECK),
KEY `TVERM~KEY` (PROGRAMM,TESTID,UCCHECK)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
update t1 set `ETEXT` = '', `ETEXT_TYPE`='', `INFO`='', `SEVERITY`='', `TADIRFLAG`=''
WHERE
`RUNID`= '' AND `SUBMITNR`= '' AND `ORDERNR`='' AND `PROGRAMM`='' AND
`TESTID`='' AND `UCCHECK`='';
drop table t1;