In 10g LINUX platform, today I executed a query which takes 5 minutes to execute. I executed the same query the next day it took long time to execute, what will be the problem?How to identify it?Tel me the solutions also.
What kind of information can be obtained from summary advisor?
Summary Advisor, a tool for choosing and understanding materialized views. The Summary Advisor helps you achieve this performance benefit by choosing the proper set of materialized views for a given w...
Performance tuning is the improvement of system performance. Performance improvement, by its nature, is iterative. The Oracle server is a sophisticated and highly tunable software product. Its flexib...
Performance tuning is the way of :Improving Throughput (in OLTP) orDecrease response time (in DWH)Different types of tuning are there:Query levelObject levelDatabase levelApplication levelSystem level...
What is the diffrence between lock and latch?
locks protect data during transactions, another process, latching, controls access to physical pages.
Latches are very lightweight, short-term synchronization objects protecting actions that do not need to be locked for the life of a transaction.
What is latch free event? When will you encounter this type of event? How will you solve it?
Latch is basically an electronic circuitory that holds the state of a system. It stores only a single bit inforamtion at a time.
The latch free Oracle metric occurs when the process is waiting for a latch held by another process (this wait event does not apply to processes that are spinning while waiting for a latch; when a pro...
How do you tune a query using explain plan?
It's just an overview of the query which tell us how this query is going to perform. But it's not actual. In most cases it's actual but it may be changed while at run time due to some fact...
Explain plan shows steps Oracle will be following to execute your query.This steps are: A) Plan steps with no children: A step in the plan with no dependents is a leaf of the tree (steps 6,7, and 9 ...
Try some indexing...