IMS - Hirerchical Database Use DL/I calls
DB2 - Relational Datsbase Use EXEC SQL stmts
In Steve Elklosin what given is
Suppose in COBOL u declared One Group item 10 times using OCCURS clause. For this already space is allocated even before the records are stored. In IMS these are stored as OCCURENCES.
And also the Parent-Child relationship can differ with DB2.
5.Modes in which IMS runs
6.Difference between these Modes and how to write Jcls for those.
7.Different Function codes for different calls available in IMS
8.Restart Logic of IMS