In a similar fashion, you can use the data dictionary view DBA_PART_KEY_COLUMNS to find
out the columns used to partition the table, as in the following example:
SQL> select owner, name, object_type, column_name,
2 column_position from DBA_PART_KEY_COLUMNS
3 where owner = 'OE' and name = 'CAT_REQ';
OWNER NAME OBJECT_TYPE COLUMN_NAME COL
--------- ------------- -------------- --------------- ---
OE CAT_REQ TABLE CAT_REQ_DT 1
1 row selected.
I will show you how to modify the partitions of a partitioned table later in this chapter, in the
section ???Managing Partitions.???
560 Oracle Database 11g DBA Handbook
Using Hash Partitioning Hash partitioning is a good option if the distribution of your data does
not easily fit into a range partitioning scheme or the number of rows in the table is unknown, but
you otherwise want to take advantage of the benefits inherent in partitioned tables. Rows are
evenly spread out to two or more partitions based on an internal hashing algorithm using the
partition key as input. The more distinct the values are in the partitioning column, the better
the distribution of rows across the partitions.
To use hash partitioning, you must specify the following three criteria:
Partitioning method (hash)
Partitioning column or columns
The number of partitions and a list of target tablespaces in which to store the partitions
For this example, you are creating a new customer table whose primary key is generated using
a sequence.
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