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SET DEFAULT_STORAGE_ENGINE = 'tokudb';
DROP TABLE IF EXISTS foo;
create table foo ( a int, b int, c int);
insert into foo values (1,1,1),(1,2,2),(1,3,3),(2,1,1),(2,2,2),(2,3,3),(3,1,1),(3,2,2),(3,3,3);
insert into foo values (4,4,1),(4,5,2),(4,6,3),(5,4,1),(5,5,2),(5,6,3),(6,4,1),(6,5,2),(6,6,3);
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
insert into foo select * from foo;
select count(*) from foo;
count(*)
36864
alter table foo add index (a), add index (b);
explain select * from foo where a=2 and b=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo index_merge a,b a,b 5,5 NULL NULL; Using intersect(a,b); Using where
alter table foo drop index a;
alter table foo add index (a) clustering=yes;
explain select * from foo where a=2 and b=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref b,a a 5 const NULL; Using where
alter table foo drop index a;
alter table foo drop index b;
alter table foo add index (a);
alter table foo add index(b) clustering=yes;
explain select * from foo where a=2 and b=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref a,b b 5 const NULL; Using where
alter table foo drop index a;
alter table foo drop index b;
alter table foo add index (a) clustering=yes, add index (b) clustering=yes;
explain select * from foo where a=2 and b=2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE foo ref a,b a 5 const NULL; Using where
DROP TABLE foo;
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