Data unavailable

Question

I have requirement as follows:
User generates a report by running a pl/sql procedure. Report is based on DB table which is deleted completely every day and data will not be available for 1 hour.
Requirement is, during this 1 hr period also user should get the report. We do not have to rewrite/alter procedure which is in production.
- Flash back option is disabled in DB
Any idea is appreciated.
Thanks in advance
Sateesh

Answer 1

Hi,
One solution i can think is ...
For an example you table name is LIVE_TABLE.
1. CREATE another table NON_LIVE_TABLE
2. CREATE VIEW which will be pointing to LIVE_TABLE and use View name in the procedure instead of table name.
SQL> create table LIVE_TABLE AS SELECT * FROM DUAL;
Table created.
SQL> create table NON_LIVE_TABLE AS SELECT * FROM DUAL;
Table created.
SQL>
SQL> CREATE VIEW FINAL_TABLE AS SELECT * FROM LIVE_TABLE;
View created.
Table TRUNCation and Data Loading:_
1. Before Loading the data Query the ALL_DEPENDENCIES view to get the dependent table name.
SQL> SELECT referenced_name from ALL_DEPENDENCIES WHERE NAME='FINAL_TABLE';
REFERENCED_NAME
LIVE_TABLE
SQL>2. Now TRUNC and LOAD data into NON_LIVE_TABLE if depenecy is on LIVE_TABLE else vice versa.
3. RECREATE the view so that it starts pointing NON_LIVE_DATA ( next day it should point LIVE_DATA).
4. Next day repeat STEP 1 to 4.
Recreation of view will take hardly few miliseconds and your reports will be available all the time.
Regards,
Avinash
Edited by: Avinash Tripathi on Dec 14, 2010 11:54 AM