关于分区表的基本概念，可以查看Oracle官方文档，链接如下：
https://docs.oracle.com/en/database/oracle/oracle-database/19/vldbg/vldb-and-partitioning-guide.pdf
Oracle® Database VLDB and Partitioning Guide
分区表使用场景：
在某些情况下，需要对表进行分区。
这里有一些建议，当你应该考虑分区一个表的情况:
•大于2 GB的表。
应该始终将这些表视为分区的候选表。
•包含历史数据的表，其中新数据被添加到最新的分区。
一个典型的例子是历史表，其中只有当前月份的数据是可更新的，其他11个月是只读的。
•表的内容必须分布在不同类型的存储设备上。
When to Partition a Table
There are certain situations when you would want to partition a table.
Here are some suggestions for situations when you should consider partitioning a table:
• Tables that are greater than 2 GB.
These tables should always be considered as candidates for partitioning.
• Tables that contain historical data, in which new data is added into the newest partition.
A typical example is a historical table where only the current month's data is updatable and the other 11 months are read only.
• Tables whose contents must be distributed across different types of storage devices.
何时对索引进行分区
在某些情况下，需要对索引进行分区。
以下是一些何时考虑对索引进行分区的建议:
•避免在删除数据时进行索引维护。
•对部分数据进行维护，而不使整个索引失效。
•减少索引对具有单调递增值的列造成的索引倾斜的影响。
When to Partition an Index
There are certain situations when you would want to partition an index.
Here are some suggestions for when to consider partitioning an index:
• Avoid index maintenance when data is removed.
• Perform maintenance on parts of the data without invalidating the entire index.
• Reduce the effect of index skew caused by an index on a column with a monotonically increasing value.
分区策略
Partitioning Strategies
Oracle Partitioning offers three fundamental data distribution methods as basic partitioning strategies that control how data is placed into individual partitions.
Oracle分区提供了三种基本的数据分布方法作为基本分区策略，用于控制如何将数据放置到各个分区中。
These strategies are:
• Range
• Hash
• List
组合分区
Composite Partitioning
Composite partitioning is a combination of the basic data distribution methods.
With composite partitioning, a table is partitioned by one data distribution method and then each partition is further subdivided into subpartitions using a second data distribution method. All subpartitions for a given partition represent a logical subset of the data.
Composite partitioning supports historical operations, such as adding new range partitions, but also provides higher degrees of potential partition pruning and finer granularity of data placement through subpartitioning. Figure 2-3 offers a graphical view of range-hash and range-list composite partitioning, as an example.
The types of composite partitioning are:
• Composite Range-Range Partitioning
• Composite Range-Hash Partitioning
• Composite Range-List Partitioning
• Composite List-Range Partitioning
• Composite List-Hash Partitioning
• Composite List-List Partitioning
• Composite Hash-Hash Partitioning
• Composite Hash-List Partitioning
• Composite Hash-Range Partitioning
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