MySQL 分区表中分区键为什么必须是主键的一部分

These features are not currently implemented in MySQL Partitioning, but are high on our list of priorities.

- Queries involving aggregate functions such as SUM() and COUNT() can easily be parallelized. A simple example of such a query might be SELECT salesperson_id, COUNT(orders) as order_total FROM sales GROUP BY salesperson_id;. By “parallelized,” we mean that the query can be run simultaneously on each partition, and the final result obtained merely by summing the results obtained for all partitions.

- Achieving greater query throughput in virtue of spreading data seeks over multiple disks.

The partition engine, used by table 'sbtest.t_range', is deprecated and will be removed in a future release. Please use native partitioning instead.

mysql> CREATE TABLE t_range (
    ->     id INT,
    ->     name VARCHAR(10)
    -> ) ENGINE = MyISAM
    -> PARTITION BY RANGE (id) (
    ->     PARTITION p0 VALUES LESS THAN (5),
    ->     PARTITION p1 VALUES LESS THAN (10)
    -> );
ERROR 1178 (42000): The storage engine for the table doesn't support native partitioning

mysql> CREATE TABLE opr (
    ->     opr_no INT,
    ->     opr_date DATETIME,
    ->     description VARCHAR(30),
    ->     PRIMARY KEY (opr_no)
    -> )
    -> PARTITION BY RANGE COLUMNS (opr_date) (
    ->     PARTITION p0 VALUES LESS THAN ('20210101'),
    ->     PARTITION p1 VALUES LESS THAN ('20210102'),
    ->     PARTITION p2 VALUES LESS THAN MAXVALUE
    -> );
ERROR 1503 (HY000): A PRIMARY KEY must include all columns in the table's partitioning function (prefixed columns are not considered).

mysql> CREATE TABLE opr (
    ->     opr_no INT,
    ->     opr_date DATETIME,
    ->     description VARCHAR(30),
    ->     PRIMARY KEY (opr_no, opr_date)
    -> )
    -> PARTITION BY RANGE COLUMNS (opr_date) (
    ->     PARTITION p0 VALUES LESS THAN ('20210101'),
    ->     PARTITION p1 VALUES LESS THAN ('20210102'),
    ->     PARTITION p2 VALUES LESS THAN MAXVALUE
    -> );
Query OK, 0 rows affected (0.04 sec)

mysql> CREATE TABLE opr (
    ->     opr_no INT,
    ->     opr_date DATETIME,
    ->     description VARCHAR(30),
    ->     PRIMARY KEY (opr_no, opr_date)
    -> )
    -> PARTITION BY RANGE COLUMNS (opr_date) (
    ->     PARTITION p0 VALUES LESS THAN ('20210101'),
    ->     PARTITION p1 VALUES LESS THAN ('20210102'),
    ->     PARTITION p2 VALUES LESS THAN MAXVALUE
    -> );
Query OK, 0 rows affected (0.04 sec)

mysql> insert into opr values(1,'2020-12-31 00:00:01','abc');
Query OK, 1 row affected (0.00 sec)

mysql> insert into opr values(1,'2021-01-01 00:00:01','abc');
Query OK, 1 row affected (0.00 sec)

mysql> select * from opr partition (p0);
+--------+---------------------+-------------+
| opr_no | opr_date            | description |
+--------+---------------------+-------------+
|      1 | 2020-12-31 00:00:01 | abc         |
+--------+---------------------+-------------+
1 row in set (0.00 sec)

mysql> select * from opr partition (p1);
+--------+---------------------+-------------+
| opr_no | opr_date            | description |
+--------+---------------------+-------------+
|      1 | 2021-01-01 00:00:01 | abc         |
+--------+---------------------+-------------+
1 row in set (0.00 sec)

mysql> create unique index uk_opr_no on opr (opr_no);
ERROR 1503 (HY000): A UNIQUE INDEX must include all columns in the table's partitioning function (prefixed columns are not considered)

Note the following characteristics of partitioned IOTs:

   - Partition columns must be a subset of primary key columns.
   - Secondary indexes can be partitioned locally and globally.
   - OVERFLOW data segments are always equipartitioned with the table partitions.

SQL> CREATE TABLE opr_oracle (
        opr_no NUMBER,
        opr_date DATE,
        description VARCHAR2(30),
       PRIMARY KEY (opr_no)
    )
    ORGANIZATION INDEX
    PARTITION BY RANGE (opr_date) (
        PARTITION p0 VALUES LESS THAN (TO_DATE('20170713', 'yyyymmdd')),
       PARTITION p1 VALUES LESS THAN (TO_DATE('20170714', 'yyyymmdd')),
       PARTITION p2 VALUES LESS THAN (MAXVALUE)
   );
PARTITION BY RANGE (opr_date) (
                    *
ERROR at line 8:
ORA-25199: partitioning key of a index-organized table must be a subset of the
primary key

SQL> CREATE TABLE opr_oracle (
        opr_no NUMBER,
        opr_date DATE,
        description VARCHAR2(30),
        PRIMARY KEY (opr_no, opr_date)
    )
    ORGANIZATION INDEX
    PARTITION BY RANGE (opr_date) (
        PARTITION p0 VALUES LESS THAN (TO_DATE('20170713', 'yyyymmdd')),
       PARTITION p1 VALUES LESS THAN (TO_DATE('20170714', 'yyyymmdd')),
       PARTITION p2 VALUES LESS THAN (MAXVALUE)
   );

Table created.

SQL> create unique index uk_opr_no on opr_oracle (opr_no);

Index created.

SQL> insert into opr_oracle values(1,to_date('2020-12-31 00:00:01','yyyy-mm-dd hh24:mi:ss'),'abc');

1 row created.

SQL> insert into opr_oracle values(1,to_date('2020-12-31 00:00:01','yyyy-mm-dd hh24:mi:ss'),'abc');
insert into opr_oracle values(1,to_date('2020-12-31 00:00:01','yyyy-mm-dd hh24:mi:ss'),'abc')
*
ERROR at line 1:
ORA-00001: unique constraint (SCOTT.SYS_IOT_TOP_87350) violated

SQL> create unique index uk_opr_no_local on opr_oracle(opr_no) local;
create unique index uk_opr_no_local on opr_oracle(opr_no) local
                                       *
ERROR at line 1:
ORA-14039: partitioning columns must form a subset of key columns of a UNIQUE
index