create table t1 (a decimal(10,4) not null, primary key(a)) engine='MYISAM' 
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=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
 PARTITION BY KEY (`a`)
(PARTITION `pa1` MAX_ROWS = 20 MIN_ROWS = 2 ENGINE = MyISAM,
 PARTITION `pa2` MAX_ROWS = 30 MIN_ROWS = 3 ENGINE = MyISAM,
 PARTITION `pa3` MAX_ROWS = 30 MIN_ROWS = 4 ENGINE = MyISAM,
 PARTITION `pa4` MAX_ROWS = 40 MIN_ROWS = 2 ENGINE = MyISAM)
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
-999999.9999
-123456.7899
-1234.5670
-1.5000
-1.0000
0.0000
1.0000
1.5000
1234.5670
123456.7899
999999.9999
select * from t1 where a=1234.567;
a
1234.5670
delete from t1 where a=1234.567;
select * from t1;
a
-999999.9999
-123456.7899
-1234.5670
-1.5000
-1.0000
0.0000
1.0000
1.5000
123456.7899
999999.9999
drop table t1;
create table t2 (a decimal(18,9) not null, primary key(a)) engine='MYISAM' 
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=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
 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
-999999999.999999999
-1234.567000000
-1.500000000
-1.000000000
0.000000000
1.500000000
1234.567000000
999999999.999999999
select * from t2 where a=1234.567;
a
1234.567000000
delete from t2 where a=1234.567;
select * from t2;
a
-999999999.999999999
-1234.567000000
-1.500000000
-1.000000000
0.000000000
1.500000000
999999999.999999999
delete from t2;
65535*3 inserts;
select count(*) from t2;
count(*)
196605
drop table t2;
create table t3 (a decimal(18,9) not null, primary key(a)) engine='MYISAM' 
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=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
 PARTITION BY RANGE (floor(`a`))
SUBPARTITION BY KEY (`a`)
SUBPARTITIONS 2
(PARTITION `pa2` VALUES LESS THAN (2) ENGINE = MyISAM,
 PARTITION `pa4` VALUES LESS THAN (4) ENGINE = MyISAM,
 PARTITION `pa6` VALUES LESS THAN (6) ENGINE = MyISAM,
 PARTITION `pa8` VALUES LESS THAN (8) ENGINE = MyISAM,
 PARTITION `pa10` VALUES LESS THAN (10) ENGINE = MyISAM)
9*3 inserts;
select count(*) from t3;
count(*)
27
drop table t3;
create table t4 (a decimal(18,9) not null, primary key(a)) engine='MYISAM' 
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=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
 PARTITION BY LIST (ceiling(`a`))
SUBPARTITION BY KEY (`a`)
SUBPARTITIONS 2
(PARTITION `pa2` VALUES IN (1,2) ENGINE = MyISAM,
 PARTITION `pa4` VALUES IN (3,4) ENGINE = MyISAM,
 PARTITION `pa6` VALUES IN (5,6) ENGINE = MyISAM,
 PARTITION `pa8` VALUES IN (7,8) ENGINE = MyISAM,
 PARTITION `pa10` VALUES IN (9,10) ENGINE = MyISAM)
9*3 inserts;
select count(*) from t4;
count(*)
27
drop table t4;