I am just listening to Robin sharma audio program, and focusing on to-do list, I got an idea on IMSDB. I decided to give some tough questions here.
IMS DB First Released in 1966
DB2 Released After IMS DB
IMS DC is the Transaction Manager Like CICS
7 Tough IMS DB Interview Questions
- In DL/I Database elements are organized in hierarchical structure. There are max 255 segments and 15 levels are possible in a database
- Q2)Top-Down-Left-Right is the approach data can be accessed-This is called sequential processing
- Q3)For Random processing, key(sequence) field is required. Through concatenated key (from root segment to the segment that you want), randomly record can be accessed.
- Q4)DL/I acts as middle layer between Application program and database. Read all imsdb posts here.
- Q5)DBD tells complete structure of the database. PSB is program’s view of the database. That means, for a DBD, multiple PSBs are possible.
- Q6)PROCOPT=G,R,I etc (check my part-1 for more on this)states access permissions on the database. Also, we can call as locks.
- Q7)ACB-also called access control block.It merges PSBs and DBDs into IMS-internal format when application program starts to execution.