To determine the amount of work and cost related to inter-instance messaging and contention, examine block transfer rates, remote requests made by each transaction, the number and time waited for global cache events as described under The response time for cache fusion transfers is determined by the messaging and processing times imposed by the physical […]
All posts by Skant Gupta
Accessing Oracle DBaaS Monitor
Database deployments of single-instance databases on Oracle Database Cloud Service include Oracle DBaaS Monitor, a built-in monitor that provides a wide spectrum of information about Oracle Database and operating system status and resource usage. You can access Oracle DBaaS Monitor in the following ways: Using the “Open DBaaS Monitor Console” menu item Using a direct […]
Difference Between Virtual Index and Invisible Index
Virtual Index Virtual indexes allow us to simulate the existence of an index and test its impact without actually building the actual index. Only sessions marked for Virtual Index usage will be affected by their existence. Their creation does not affect new sessions. Virtual indexes will be used only when the initialization parameter “_use_nosegment_indexes” is […]
Virtual Index or Fake Index in Oracle
Oracle has come up with a feature called virtual index in oracle 9i. This feature allow us to test an index on a table without actually adding an index on the table. The table will be visible only in our session and will be used by our queries only (if optimizer decide it to use). […]
What happens in the background in Rebuild Index
I must thank my fellow DBA Franky Weber Faust for his publication in his blog. I’ll show you what happens during an online rebuild of an index. Few DBAs realize this, but during this operation an auxiliary index (among other things) is created to store the transient data while the application continues to run normally. Note that for […]
Create an Oracle SQL TUNING TASK with DBMS_SQLTUNE
You can create an SQL TUNING TASK manually adhoc with the following simple steps. Step1: Find the sql_id of the oracle session you would like to analyze. Usually the AWR has the top sql_ids. In case this is a current sql running use the v$session. select sql_id from v$session where sid = 😡 Step2: Login […]
How to extract SQL from SQLT
SQLTXPLAIN gets installed into separate schema called SQLTXPLAIN. It can be installed on RAC and on any version greater than 9i. When it is installed, it will ask for application schema so make sure that installation schema has SELECT_CATALOG_ROLE privilege. In order to run the script to create SQLTXPLAIN schema, one need to connect as […]
LOCAL=NO & LOCAL=YES in Oracle
LOCAL = NO: non-local connection, namely a network connection. Listener connect to the server. Client application through the client listener listener sends a request to the server, the server listens received in connection with the database, perform related operations, the results returned to the client. This is the process by listening. So you need to […]
Oracle Database Maximum Availability Certified Expert
Hi Readers Finally I’ve successfully achieved Oracle Database Maximum Availability Certified Expert. It was almost more than 6 months that I’ve been preparing for this. To achieve this certification, we must complete ALL the three certifications: Oracle Database 12c Administrator Certified Professional Oracle Certified Expert, Oracle Database 12c: RAC and Grid Infrastructure Administration Oracle Certified Expert, Oracle Database […]
Oracle DBaaS Monitor In Oracle Cloud
Oracle DBaaS Monitor provides monitoring and management of the Oracle database and listener on Oracle Database Cloud Service. DBaaS Monitor provides quick and easy access to a variety of information about the database instance running on a database deployment: Overall, how much storage is allocated to tablespaces, and how much of that storage is used For […]