# include/index_merge1.inc
#
# Index merge tests
#
# The variable
# $merge_table_support -- 1 storage engine supports merge tables
# -- 0 storage engine does not support merge tables
# has to be set before sourcing this script.
#
# Note: The comments/expectations refer to MyISAM.
# They might be not valid for other storage engines.
#
# Last update:
# 2006-08-02 ML test refactored
# old name was t/index_merge.test
# main code went into include/index_merge1.inc
#
--source include/have_sequence.inc
--echo #---------------- Index merge test 1 -------------------------------------------
# Create and fill a table with simple keys
create table t0
(
key1 int not null,
INDEX i1(key1)
);
insert into t0(key1) select seq from seq_1_to_1024;
alter table t0 add key2 int not null, add index i2(key2);
alter table t0 add key3 int not null, add index i3(key3);
alter table t0 add key4 int not null, add index i4(key4);
alter table t0 add key5 int not null, add index i5(key5);
alter table t0 add key6 int not null, add index i6(key6);
alter table t0 add key7 int not null, add index i7(key7);
alter table t0 add key8 int not null, add index i8(key8);
update t0 set key2=key1,key3=key1,key4=key1,key5=key1,key6=key1,key7=key1,key8=1024-key1;
analyze table t0;
# 1. One index
explain select * from t0 where key1 < 3or key1 > 920and key1 < 924;
# 2. Simple cases
explain
select * from t0 where key1 < 3or key2 > 920and key2 < 924;
select * from t0 where key1 < 3or key2 > 920and key2 < 924;
select * from t0 where key1=1022; # MDEV-13535 no-key-read select after keyread
explain select * from t0 where key1 < 3or key2 <4;
explain
select * from t0 where (key1 > 30and key1<35) or (key2 >32and key2 < 40);
# Bug#21277: InnoDB, wrong result set, index_merge strategy, second index not evaluated
select * from t0 where (key1 > 30and key1<35) or (key2 >32and key2 < 40);
# 3. Check that index_merge doesn't break "ignore/force/use index"
explain select * from t0 ignore index (i2) where key1 < 3or key2 <4;
explain select * from t0 where (key1 < 3or key2 <4) and key3 = 50;
explain select * from t0 use index (i1,i2) where (key1 < 3or key2 <4) and key3 = 50;
explain select * from t0 where (key1 > 1or key2 > 2);
explain select * from t0 force index (i1,i2) where (key1 > 1or key2 > 2);
# 4. Check if conjuncts are grouped by keyuse
explain
select * from t0 where key1<3or key2<3or (key1>5and key1<8) or
(key1>10and key1<12) or (key2>100and key2<110);
# 5. Check index_merge with conjuncts that are always true/false
# verify fallback to"range"if there is only one non-confluent condition
explain select * from t0 where key2 = 45or key1 <=> null;
explain select * from t0 where key2 = 45or key1 isnot null;
explain select * from t0 where key2 = 45or key1 is null;
# the last conj. is always false and will be discarded
explain select * from t0 where key2=10or key3=3or key4 <=> null;
# the last conj. is always true and will cause 'all' scan
explain select * from t0 where key2=10or key3=3or key4 is null;
# some more complicated cases
explain select key1 from t0 where (key1 <=> null) or (key2 < 5) or
(key3=10) or (key4 <=> null);
explain select key1 from t0 where (key1 <=> null) or (key1 < 5) or
(key3=10) or (key4 <=> null);
# 6.Several ways todo index_merge, (ignored) index_merge vs. range
explain select * from t0 where
(key1 < 3or key2 < 3) and (key3 < 4or key4 < 4) and (key5 < 5or key6 < 5);
explain
select * from t0 where (key1 < 3or key2 < 6) and (key1 < 7or key3 < 4);
select * from t0 where (key1 < 3or key2 < 6) and (key1 < 7or key3 < 4);
explain select * from t0 where
(key1 < 3or key2 < 3) and (key3 < 4or key4 < 4) and (key5 < 2or key6 < 2);
# now index_merge isnot used at all when "range"is possible
explain select * from t0 where
(key1 < 3or key2 < 3) and (key3 < 100);
# this even can cause "all" scan:
explain select * from t0 where
(key1 < 3or key2 < 3) and (key3 < 1000);
# 7. Complex cases
# tree_or(List<SEL_IMERGE>, range SEL_TREE).
explain select * from t0 where
((key1 < 4or key2 < 4) and (key2 <5or key3 < 4)) or
key2 > 5;
explain select * from t0 where
((key1 < 4or key2 < 4) and (key2 <5or key3 < 4)) or
key1 < 7;
select * from t0 where
((key1 < 4or key2 < 4) and (key2 <5or key3 < 4)) or
key1 < 7;
# tree_or(List<SEL_IMERGE>, List<SEL_IMERGE>).
select count(*) from t0 where
((key1 < 4or key2 < 4) and (key3 <5or key5 < 4)) or
((key5 < 5or key6 < 6) and (key7 <7or key8 < 4));
explain select * from t0 where
((key1 < 4or key2 < 4) and (key3 <5or key5 < 4)) or
((key5 < 5or key6 < 6) and (key7 <7or key8 < 4));
explain select * from t0 where
((key3 <5or key5 < 4) and (key1 < 4or key2 < 4)) or
((key7 <7or key8 < 4) and (key5 < 5or key6 < 6));
explain select * from t0 where
((key3 <5or key5 < 4) and (key1 < 4or key2 < 4)) or
((key3 <7or key5 < 2) and (key5 < 5or key6 < 6));
explain select * from t0 where
((key3 <5or key5 < 4) and (key1 < 4or key2 < 4)) or
(((key3 <7and key7 < 6) or key5 < 2) and (key5 < 5or key6 < 6));
explain select * from t0 where
((key3 < 4or key5 < 4) and (key1 < 4or key2 < 4)) or
((key3 >=5or key5 < 2) and (key5 < 5or key6 < 6));
explain select * from t0 force index(i1, i2, i3, i4, i5, i6 ) where
((key3 < 4or key5 < 4) and (key1 < 4or key2 < 4)) or
((key3 >=5or key5 < 2) and (key5 < 5or key6 < 6));
explain select * from t0 force index(i1, i2, i3, i4, i5, i6 ) where
((key3 < 5or key5 < 4) and (key1 < 4or key2 < 4)) or
((key3 >=5or key5 < 2) and (key5 < 5or key6 < 6));
explain select * from t0 force index(i1, i2, i3, i4, i5, i6 ) where
((key3 < 10or key5 < 4) and (key1 < 4or key2 < 4)) or
((key3 >=5or key5 < 2) and (key5 < 5or key6 < 6));
# 8. Verify that "order by" after index merge uses filesort
select * from t0 where key1 < 5or key8 < 4 order by key1;
explain
select * from t0 where key1 < 5or key8 < 4 order by key1;
# 9. Check that index_merge cost is compared to'index' where possible
create table t2 like t0;
insert into t2 select * from t0;
alter table t2 add index i1_3(key1, key3);
alter table t2 add index i2_3(key2, key3);
alter table t2 drop index i1;
alter table t2 drop index i2;
alter table t2 add index i321(key3, key2, key1);
# index_merge vs 'index', index_merge is better.
explain select key3 from t2 where key1 = 100or key2 = 100;
# index_merge vs 'index', 'index'is better.
explain select key3 from t2 where key1 < 600or key2 < 600;
# index_merge vs 'all', index_merge is better.
explain select key7 from t2 where key1 <100or key2 < 100;
# 10. Multipart keys.
create table t4 (
key1a int not null,
key1b int not null,
key2 int not null,
key2_1 int not null,
key2_2 int not null,
key3 int not null,
index i1a (key1a, key1b),
index i1b (key1b, key1a),
index i2_1(key2, key2_1),
index i2_2(key2, key2_1)
);
insert into t4 select seq,seq,seq div10, seq % 10, seq % 10, seq from seq_1_to_1024;
# the following will be handled by index_merge:
select * from t4 where key1a = 3or key1b = 4;
explain select * from t4 where key1a = 3or key1b = 4;
# and the following will not
explain select * from t4 where key2 = 1and (key2_1 = 1or key3 = 5);
explain select * from t4 where key2 = 1and (key2_1 = 1or key2_2 = 5);
explain select * from t4 where key2_1 = 1or key2_2 = 5;
# 11. Multitable selects
create table t1 like t0;
insert into t1 select * from t0;
# index_merge on first table in join
explain select * from t0 left join t1 on (t0.key1=t1.key1)
where t0.key1=3or t0.key2=4;
select * from t0 left join t1 on (t0.key1=t1.key1)
where t0.key1=3or t0.key2=4;
explain
select * from t0,t1 where (t0.key1=t1.key1) and ( t0.key1=3or t0.key2=4);
# index_merge vs. ref
explain
select * from t0,t1 where (t0.key1=t1.key1) and
(t0.key1=3or t0.key2=4) and t1.key1<200;
# index_merge vs. ref
explain
select * from t0,t1 where (t0.key1=t1.key1) and
(t0.key1=3or t0.key2<4) and t1.key1=2;
# index_merge on second table in join
explain select * from t0,t1 where t0.key1 = 5and
(t1.key1 = t0.key1 or t1.key8 = t0.key1);
# Fix for bug#1974
explain select * from t0,t1 where t0.key1 < 3and
(t1.key1 = t0.key1 or t1.key8 = t0.key1);
# index_merge inside union
explain select * from t1 where key1=3or key2=4
union select * from t1 where key1<4or key3=5;
# index merge in subselect set @tmp_optimizer_switch=@@optimizer_switch; set optimizer_switch='derived_merge=off,derived_with_keys=off';
explain select * from (select * from t1 where key1 = 3or key2 =3) as Z where key8 >5; set optimizer_switch=@tmp_optimizer_switch;
# 12. check for long index_merges.
create table t3 like t0;
insert into t3 select * from t0;
alter table t3 add key9 int not null, add index i9(key9);
alter table t3 add keyA int not null, add index iA(keyA);
alter table t3 add keyB int not null, add index iB(keyB);
alter table t3 add keyC int not null, add index iC(keyC);
update t3 set key9=key1,keyA=key1,keyB=key1,keyC=key1;
explain select * from t3 where
key1=1or key2=2or key3=3or key4=4or
key5=5or key6=6or key7=7or key8=8or
key9=9or keyA=10or keyB=11or keyC=12;
select * from t3 where
key1=1or key2=2or key3=3or key4=4or
key5=5or key6=6or key7=7or key8=8or
key9=9or keyA=10or keyB=11or keyC=12;
# Test for Bug#3183
explain select * from t0 where key1 < 3or key2 < 4;
# Bug#21277: InnoDB, wrong result set, index_merge strategy, second index not evaluated
select * from t0 where key1 < 3or key2 < 4;
update t0 set key8=123 where key1 < 3or key2 < 4;
# Bug#21277: InnoDB, wrong result set, index_merge strategy, second index not evaluated
select * from t0 where key1 < 3or key2 < 4;
delete from t0 where key1 < 3or key2 < 4;
select * from t0 where key1 < 3or key2 < 4;
select count(*) from t0;
# Test for BUG#4177
drop table t4;
create table t4 (a int);
insert into t4 values (1),(4),(3); set @save_join_buffer_size=@@join_buffer_size; set join_buffer_size= 4096;
explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) as exp
from t0 as A force index(i1,i2), t0 as B force index (i1,i2)
where (A.key1 < 500000or A.key2 < 3) and (B.key1 < 500000or B.key2 < 3);
select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) as exp
from t0 as A force index(i1,i2), t0 as B force index (i1,i2)
where (A.key1 < 500000or A.key2 < 3) and (B.key1 < 500000or B.key2 < 3);
update t0 set key1=1;
explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) as exp
from t0 as A force index(i1,i2), t0 as B force index (i1,i2)
where (A.key1 = 1or A.key2 = 1) and (B.key1 = 1or B.key2 = 1);
select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) as exp
from t0 as A force index(i1,i2), t0 as B force index (i1,i2)
where (A.key1 = 1or A.key2 = 1) and (B.key1 = 1or B.key2 = 1);
alter table t0 add filler1 char(200), add filler2 char(200), add filler3 char(200);
update t0 set key2=1, key3=1, key4=1, key5=1,key6=1,key7=1 where key7 < 500;
# The next query will not use index i7 in intersection if the OS doesn't
# support file sizes > 2GB. (ha_myisam::ref_length depends on this and index
# scan cost estimates depend on ha_myisam::ref_length)
--replace_column 9 #
--replace_result "4,4,4,4,4,4,4" X "4,4,4,4,4,4" X "i6,i7""i6,i7?""i6""i6,i7?"
explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) as exp
from t0 as A straight_join t0 as B
where (A.key1 = 1and A.key2 = 1and A.key3 = 1and A.key4=1and A.key5=1and A.key6=1and A.key7 = 1or A.key8=1) and (B.key1 = 1and B.key2 = 1and B.key3 = 1and B.key4=1and B.key5=1and B.key6=1and B.key7 = 1orB.key8=1);
select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) as exp
from t0 as A straight_join t0 as B
where (A.key1 = 1and A.key2 = 1and A.key3 = 1and A.key4=1and A.key5=1and A.key6=1and A.key7 = 1or A.key8=1) and (B.key1 = 1and B.key2 = 1and B.key3 = 1and B.key4=1and B.key5=1and B.key6=1and B.key7 = 1orB.key8=1);
set join_buffer_size= @save_join_buffer_size;
# Test for BUG#4177 ends
drop table t0, t1, t2, t3, t4;
# BUG#16166
CREATE TABLE t1 (
cola char(3) not null, colb char(3) not null, filler char(200),
key(cola), key(colb)
);
INSERT INTO t1 VALUES ('foo','bar', 'ZZ'),('fuz','baz', 'ZZ');
--disable_query_log
let $1=9; begin; while ($1)
{
eval INSERT INTO t1 SELECT * from t1 WHERE cola = 'foo';
dec $1;
}
let $1=13; while ($1)
{
eval INSERT INTO t1 SELECT * from t1 WHERE cola <> 'foo';
dec $1;
}
commit;
--enable_query_log
OPTIMIZE TABLE t1;
select count(*) from t1;
explain select * from t1 WHERE cola = 'foo'AND colb = 'bar';
explain select * from t1 force index(cola,colb) WHERE cola = 'foo'AND colb = 'bar';
drop table t1;
if ($merge_table_support)
{
#
# BUG#17314: Index_merge/intersection not chosen by the optimizer for MERGE tables
#
create table t1 (
a int, b int,
filler1 char(200), filler2 char(200),
key(a),key(b)
);
insert into t1 select @v:= seq % 10, @v, 't1', 'filler2' from seq_1_to_1000;
create table t2 like t1;
create table t3 (
a int, b int,
filler1 char(200), filler2 char(200),
key(a),key(b)
) engine=merge union=(t1,t2);
--replace_column 9 #
explain select * from t1 where a=1and b=1;
--replace_column 9 #
explain select * from t3 where a=1and b=1;
create table t2(
`a` int(11) DEFAULT NULL,
`filler` char(200) DEFAULT NULL,
`b` int(11) DEFAULT NULL,
KEY USING BTREE (`a`),
KEY USING BTREE (`b`)
) ENGINE=MEMORY DEFAULT CHARSET=latin1;
insert into t2 select * from t1;
--echo must use sort-union rather than union:
--replace_column 9 #
explain select * from t1 where a=4or b=4;
--sorted_result
select * from t1 where a=4or b=4;
--sorted_result
select * from t1 ignore index(a,b) where a=4or b=4;
--echo must use union, not sort-union:
--replace_column 9 #
explain select * from t2 where a=2or b=2;
--sorted_result
select * from t2 where a=2or b=2;
drop table t1, t2;
#
# Bug #37943: Reproducible mysqld crash/sigsegv in sel_trees_can_be_ored
#
CREATE TABLE t1 (a varchar(8), b set('a','b','c','d','e','f','g','h'),
KEY b(b), KEY a(a));
INSERT INTO t1 VALUES ('y',''), ('z','');
#should not crash
SELECT b,a from t1 WHERE (b!='c'AND b!='f' && b!='h') OR
(a='pure-S') OR (a='DE80337a') OR (a='DE80799');
DROP TABLE t1;
--echo #
--echo # BUG#40974: Incorrect query results when using clause evaluated using range check
--echo #
create table t1 (a int);
insert into t1 values (1),(2);
create table t2(a int, b int);
insert into t2 values (1,1), (2, 1000),(5000,5000);
create table t3 (a int, b int, filler char(100), key(a), key(b));
insert into t3 select 1000, 1000,'filler' from seq_1_to_1000;
insert into t3 values (1,1,'data');
insert into t3 values (1,1,'data');
-- echo The plan should be ALL/ALL/ALL(Range checked for each record (index map: 0x3)
explain select * from t1
where exists (select 1 from t2, t3
where t2.a=t1.a and (t3.a=t2.b or t3.b=t2.b or t3.b=t2.b+1));
select * from t1
where exists (select 1 from t2, t3
where t2.a=t1.a and (t3.a=t2.b or t3.b=t2.b or t3.b=t2.b+1));
drop table t1, t2, t3;
--echo #
--echo # BUG#44810: index merge and order by withlow sort_buffer_size
--echo # crashes server!
--echo #
CREATE TABLE t1(a VARCHAR(128),b VARCHAR(128),KEY(A),KEY(B));
INSERT INTO t1 SELECT REPEAT('a',128),REPEAT('b',128) FROM seq_1_to_64; SET SESSION sort_buffer_size=1024*8;
EXPLAIN
SELECT * FROM t1 FORCE INDEX(a,b) WHERE a LIKE 'a%'OR b LIKE 'b%'
ORDER BY a,b;
# we don't actually care about the result : we're checking if it crashes
--disable_result_log
SELECT * FROM t1 FORCE INDEX(a,b) WHERE a LIKE 'a%'OR b LIKE 'b%'
ORDER BY a,b;
--enable_result_log
SET SESSION sort_buffer_size=DEFAULT;
DROP TABLE t1;
--echo Endof5.0 tests
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.17 Sekunden
(vorverarbeitet am 2026-10-08)
¤
Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
noch Qualität der bereit gestellten Informationen zugesichert.
Bemerkung:
Die farbliche Syntaxdarstellung und die Messung sind noch experimentell.