create table t1 (a decimal(10,4) not null, primary key(a)) engine='InnoDB' 
partition by key (a) (
partition pa1 max_rows=20 min_rows=2,
partition pa2 max_rows=30 min_rows=3,
partition pa3 max_rows=30 min_rows=4,
partition pa4 max_rows=40 min_rows=2);
show create table t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `a` decimal(10,4) NOT NULL,
  PRIMARY KEY (`a`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
/*!50100 PARTITION BY KEY (a)
(PARTITION pa1 MAX_ROWS = 20 MIN_ROWS = 2 ENGINE = InnoDB,
 PARTITION pa2 MAX_ROWS = 30 MIN_ROWS = 3 ENGINE = InnoDB,
 PARTITION pa3 MAX_ROWS = 30 MIN_ROWS = 4 ENGINE = InnoDB,
 PARTITION pa4 MAX_ROWS = 40 MIN_ROWS = 2 ENGINE = InnoDB) */
insert into t1 values (999999.9999), (-999999.9999), (123456.7899), (-123456.7899), (-1.5), (1), (0), (-1), (1.5), (1234.567), (-1234.567);
select * from t1;
a
-1234.5670
123456.7899
-999999.9999
-123456.7899
0.0000
1234.5670
-1.5000
-1.0000
1.0000
999999.9999
1.5000
select * from t1 where a=1234.567;
a
1234.5670
delete from t1 where a=1234.567;
select * from t1;
a
-1234.5670
123456.7899
-999999.9999
-123456.7899
0.0000
-1.5000
-1.0000
1.0000
999999.9999
1.5000
drop table t1;
create table t2 (a decimal(18,9) not null, primary key(a)) engine='InnoDB' 
partition by key (a) partitions 10;
show create table t2;
Table	Create Table
t2	CREATE TABLE `t2` (
  `a` decimal(18,9) NOT NULL,
  PRIMARY KEY (`a`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
/*!50100 PARTITION BY KEY (a)
PARTITIONS 10 */
insert into t2 values (999999999.999999999), (-999999999.999999999), (-1.5), (-1), (0), (1.5), (1234.567), (-1234.567);
select * from t2;
a
-1234.567000000
-999999999.999999999
1.500000000
1234.567000000
-1.000000000
-1.500000000
999999999.999999999
0.000000000
select * from t2 where a=1234.567;
a
1234.567000000
delete from t2 where a=1234.567;
select * from t2;
a
-1234.567000000
-999999999.999999999
1.500000000
-1.000000000
-1.500000000
999999999.999999999
0.000000000
delete from t2;
1024*3 inserts;
select count(*) from t2;
count(*)
3072
drop table t2;
create table t3 (a decimal(18,9) not null, primary key(a)) engine='InnoDB' 
partition by range (floor(a)) subpartition by key (a) subpartitions 2 (
partition pa2 values less than (2),
partition pa4 values less than (4),
partition pa6 values less than (6),
partition pa8 values less than (8),
partition pa10 values less than (10)
);
show create table t3;
Table	Create Table
t3	CREATE TABLE `t3` (
  `a` decimal(18,9) NOT NULL,
  PRIMARY KEY (`a`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
/*!50100 PARTITION BY RANGE (floor(a))
SUBPARTITION BY KEY (a)
SUBPARTITIONS 2
(PARTITION pa2 VALUES LESS THAN (2) ENGINE = InnoDB,
 PARTITION pa4 VALUES LESS THAN (4) ENGINE = InnoDB,
 PARTITION pa6 VALUES LESS THAN (6) ENGINE = InnoDB,
 PARTITION pa8 VALUES LESS THAN (8) ENGINE = InnoDB,
 PARTITION pa10 VALUES LESS THAN (10) ENGINE = InnoDB) */
9*3 inserts;
insert into t3 values (9);
insert into t3 values (9+0.333333333);
insert into t3 values (9+0.755555555);
insert into t3 values (8);
insert into t3 values (8+0.333333333);
insert into t3 values (8+0.755555555);
insert into t3 values (7);
insert into t3 values (7+0.333333333);
insert into t3 values (7+0.755555555);
insert into t3 values (6);
insert into t3 values (6+0.333333333);
insert into t3 values (6+0.755555555);
insert into t3 values (5);
insert into t3 values (5+0.333333333);
insert into t3 values (5+0.755555555);
insert into t3 values (4);
insert into t3 values (4+0.333333333);
insert into t3 values (4+0.755555555);
insert into t3 values (3);
insert into t3 values (3+0.333333333);
insert into t3 values (3+0.755555555);
insert into t3 values (2);
insert into t3 values (2+0.333333333);
insert into t3 values (2+0.755555555);
insert into t3 values (1);
insert into t3 values (1+0.333333333);
insert into t3 values (1+0.755555555);
select count(*) from t3;
count(*)
27
drop table t3;
create table t4 (a decimal(18,9) not null, primary key(a)) engine='InnoDB' 
partition by list (ceiling(a)) subpartition by key (a) subpartitions 2 (
partition pa2 values in (1,2),
partition pa4 values in (3,4),
partition pa6 values in (5,6),
partition pa8 values in (7,8),
partition pa10 values in (9,10)
);
show create table t4;
Table	Create Table
t4	CREATE TABLE `t4` (
  `a` decimal(18,9) NOT NULL,
  PRIMARY KEY (`a`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
/*!50100 PARTITION BY LIST (ceiling(a))
SUBPARTITION BY KEY (a)
SUBPARTITIONS 2
(PARTITION pa2 VALUES IN (1,2) ENGINE = InnoDB,
 PARTITION pa4 VALUES IN (3,4) ENGINE = InnoDB,
 PARTITION pa6 VALUES IN (5,6) ENGINE = InnoDB,
 PARTITION pa8 VALUES IN (7,8) ENGINE = InnoDB,
 PARTITION pa10 VALUES IN (9,10) ENGINE = InnoDB) */
9*3 inserts;
insert into t4 values (9);
insert into t4 values (9+0.333333333);
insert into t4 values (9+0.755555555);
insert into t4 values (8);
insert into t4 values (8+0.333333333);
insert into t4 values (8+0.755555555);
insert into t4 values (7);
insert into t4 values (7+0.333333333);
insert into t4 values (7+0.755555555);
insert into t4 values (6);
insert into t4 values (6+0.333333333);
insert into t4 values (6+0.755555555);
insert into t4 values (5);
insert into t4 values (5+0.333333333);
insert into t4 values (5+0.755555555);
insert into t4 values (4);
insert into t4 values (4+0.333333333);
insert into t4 values (4+0.755555555);
insert into t4 values (3);
insert into t4 values (3+0.333333333);
insert into t4 values (3+0.755555555);
insert into t4 values (2);
insert into t4 values (2+0.333333333);
insert into t4 values (2+0.755555555);
insert into t4 values (1);
insert into t4 values (1+0.333333333);
insert into t4 values (1+0.755555555);
select count(*) from t4;
count(*)
27
drop table t4;