hi i am new to IMS DB/DC i am studying this form IMS FOR THE COBOL PROGRAMMING by steve eckolos.......but i would like to know the structure of IMS data base just like DB2 as tables........
and also actually what is physical and logical database
Joined: 28 Mar 2005 Posts: 1509 Location: Chicago, IL
Hi Kamalak,
Quote:
i would like to know the structure of IMS data base just like DB2 as tables........
IMS is a Hierarchical Database, while DB2 is a Relational Database.
In IMS, data is stored in hierarchical manner.
There is a parent segment which can have multiple child segments. They are known as Siblings in IMS Terms.
There can be more than one occurrences of a child for Parent, such occurrences are known as Twins in IMS.
Quote:
and also actually what is physical and logical database
You are going thru Steve Eckols....You'll come across a term in IMS called PSB. PSB defines some part of the database to be accessed. You create & use PSB's as per your Database need. This PSB can be referred as Logical Database for IMS.
