1) What is the physical nature of a database called?
2) Is it necessary that all the segments in a Dl/i database have key fields?
A) It is not necessary that all the segments in the database should have key field, expect for the database.
3) How man key fields and search fields can a segment have?
A) One key field and as many search fields in the segment can be declared.
4) Is it necessary that the key field in a Dl/I database be unique?
A) No, it is no necessary.
5) What is a key field in an IMS database?
A) A Field that DL/I uses to maintain the segments in the ascending order is called the key field
6) What is a database record?
A) A single occurrence of the root along with all its dependents is called the database record.
7) What is a Hierarchy path?
A) A line that starts at the root and passes thru the inter mediate levels in the hierarchy and ends at the a segment at the bottom of the hierarchy is called the Hierarchy path.
8) What is a Root?
A) The segment at the top of the Hierarchy, which is not a child to a segment is called the Root.
9) What are Twins?
A) Occurrences of all the segment types under a single parent segment occurrence is called a Twin.
10) Define the terms Parent & Child.
A) Parent-Any segment that has one or more segments directly below it is a Parent. Child-Any segment that has segment directly above it is called the Child.
11) What is the limitation on the no. of levels in a DL/I database?
A) You can have 15 levels in a DL/I database
12) How many sgment types can u have in a DL/I database?
A) A Dl/I database can have 255 segment types
13) What is a Segment type?
A) Loosely speaking a segment type is a segment in a Dl/I hierarchy chart.
14) What is a segment?
A) A segment is the smallest unit of information that Dl/I uses when working with information in the database
15) What is Hierarchy Chart?
A) A Hierarchy chart is a pictorial representation of the total of a DL/I database starting from the root, giving all the parent child relationships that exist within the database