Difference between Physical & Logical instances


By naveenkumar_segu - Wednesday, January 26, 2011 11:11 PM


I have heard two phrases from someone "Physical & Logical instances". Can anyone please explain me what this is?

Thank you all.

By GilaMonster - Wednesday, January 26, 2011 11:20 PM

No such thing as a physical or logical instance of SQL. Could be something unrelated. Why don't you ask the person that you heard it from?
By Pouliot Philippe - Wednesday, January 26, 2011 11:25 PM

Physcial or Logical exist for Oracle.

1. Physical Standby Database

Standby database is called “physical” if the physical structure of stand by exactly matches with stand by structure. Archived redo log transferred from primary database will be directly applied to the stand by database.

2. Logical Standby Database

Stand by database is called “logical”, the physical structure of both
databases do not match and from the archived redo log we create SQL statements then these statements will be applied to stand by database.

By george sibbald - Wednesday, January 26, 2011 11:50 PM

they might have a meant a 'virtual' instance, which is what a sql instance is referred to in a clustered configuration as it could reside on more than one physical node.
By sqlbuddy123 - Thursday, January 27, 2011 3:24 AM

Or Could be a Instance on a Virtual Machine Vs Instance on a Physical Machine

Thank You,

Best Regards,