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Oracle Tips
by Burleson Consulting
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The Data Warehouse Development Life Cycle
Distributed Oracle Data Warehouses
Real-time table updates
CREATE SNAPSHOT unfilled_orders
REFRESH COMPLETE
START WITH TO_DATE ('DD-MON-YY HH23:MI:55)
NEXT SYSDATE + 7
AS
SELECT customer_name, customer_address, order_date
FROM customer@paris, order@london
SEE CODE DEPOT FOR FULL SCRIPT
order_complete_flag = "N";
Here, you can see that a snapshot will be taken on Monday at 11:55
PM, and, thereafter, every seven days. The end users will be told
about the refreshing period, and the database software will
automatically perform the extract. The Remote DBA could also perform the
extract manually by issuing the following command:
EXECUTE
unfilled_orders.refreash_all;
Now, let’s take a detailed look at how Oracle snapshots are used to
replicate tables.
This is an excerpt from "High Performance
Data Warehousing", copyright 1997.
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