在数据库分区环境中，需要为DB 2创建三个组和用户ID，如下表所示。

In a database partitioning environment, you need to create three groups and user IDs for DB2. They are shown in the table below.

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于是DB 2就可以在存储数据的数据库分区上执行连接或子查询，而不必在数据库分区之间移动数据。

DB2 can then choose to perform the join or subquery at the database partition where the data is stored, instead of having to move data between database partitions.

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distinct值的数量必须多到足以确保数据行均匀地分布在数据库分区组中的所有数据库分区上。

The number of distinct values must be great enough to ensure an even distribution of rows across all database partitions in the database partition group.

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