Best way to remove old data from db?

Question

Hi,
I am looking some ways to keep my database small and remove old data from database and archive it somewhere else. the data may need to be put back to the database in the future. One of the things I am conserned is how to enforce constraints? In other words, when I remove data, all the related pk/fk data should be removed together. Any suggestions will be greatly appreciated.
Thanks

Answer 1

hope this may help u
concept is : exp/imp & truncate will reclaim the space
method1
do an export and secure the dump(say dump1) for future purpose.
delete the unwanted data.
commit.
now again export the tables ( say dump2).
now do the import(dump2).
/*now this import will reclaim the the unused space.*/
method 2
/* depennded on volume of data */
-- create backup of existing table for future
create table backup_table nologging as select * from original_table;
-- create copy1 of existing table
create table copy_table nologging as select * from original_table;
-- truncate the original table, so that highwater mark is reset.
truncate table original_table;
-- insert data from copy_table into original table
insert /*+ APPEND */ into original_table select * copy_table where(ur conditions for data);
commit all the work.
/* now u have 3 tables
backup_table - with all the data - for future reload
original_table - with unwanted data deleted and space reclaimed.
copy_table - copy of original table.
now u drop the copy_table
drop table copy_table;
regards