| URGENT HELP Needed ! - Please [message #52023] |
Wed, 26 June 2002 13:39  |
saravan
Messages: 1
Registered: June 2002
|
Junior Member |
|
|
Hello all,
I have got couple of questions and need some help.
Question 1:
I got two servers one local one remote and a db link for the remote server. Tables are named as 'TP' in local and 'TPR' in remote. TP has 1000 rows and TPR has 5000 ROWS. I am trying to do a equijoin between 'TP' and remote table 'TPR' using the DBlink.
Now could you please tell me how does the oracle know which way to go ?. That is take all 1000 rows and compare it one by one against 5000 rows on remote table or vice versa ?.
Question 2:
Which one is better Materilised View or ETL and why ?
Question 3:
How to avoid/minimize the pinging in OPS environment ?
Any help would be very much appreciated.
Thanks,
Saravan
|
|
|
|
| Re: URGENT HELP Needed ! - Please [message #52024 is a reply to message #52023] |
Wed, 26 June 2002 13:50  |
Trifon Anguelov
Messages: 514
Registered: June 2002
|
Senior Member |
|
|
1. That depends on your SQL query (execution plan). get the plan and see it for yourself. The order of the tables in the FROM clause and the joins in the WHERE clause, determine this order.
2. Materialized view, because you build it once and then only update it. It is less expensive in a sence of CPU and I/O.
3. Upgrade to Oracle 9i RAC - it has cache fusion, which eliminates the block pinging.
Hope that helps,
clio_usa
OCP - DBA
Visit our web site [url=http://www.dbaclick.com]Click Here
|
|
|
|
] 
Blog
Search
Help
Members
Register
Login
Home
