Apress.Expert.Oracle.Database.Architecture.9i.and.10g.Programming.Techniques.and.Solutions.Sep.2005

CHAPTER 13 ■ PARTITIONING 595
Now we’re ready to update the “live” data using an exchange partition:
ops$tkyte@ORA10G> alter table partitioned
2 exchange partition fy_2004
3 with table fy_2004
4 including indexes
5 without validation
6 /
Table altered.
ops$tkyte@ORA10G> alter table partitioned
2 drop partition fy_2004
3 /
Table altered.
This is all we need to do to “age” the old data out. We turned the partition into a full
table and the empty table into a partition. This was a simple data dictionary update. No large
amount of I/O took place—it just happened. We can now export that FY_2004 table (perhaps
using a transportable tablespace) out of our database for archival purposes. We could reattach
it quickly if we ever needed to.
Next, we want to slide in the new data:
ops$tkyte@ORA10G> alter table partitioned
2 add partition fy_2006
3 values less than ( to_date('01-jan-2007','dd-mon-yyyy') )
4 /
Table altered.
ops$tkyte@ORA10G> alter table partitioned
2 exchange partition fy_2006
3 with table fy_2006
4 including indexes
5 without validation
6 /
Table altered.
Again, this was instantaneous; it was accomplished via simple data dictionary updates.
Adding the empty partition took very little time to process. Then, we exchange the newly created
empty partition with the full table, and the full table with the empty partition, and that
operation is performed quickly as well. The new data is online.
Looking at our indexes, however, we’ll find the following:
ops$tkyte@ORA10G> select index_name, status from user_indexes;
INDEX_NAME
STATUS
------------------------------ --------
FY_2006_IDX
VALID
FY_2004_IDX
VALID
PARTITIONED_IDX_GLOBAL UNUSABLE