Question

In DBMS, what would you use to obtain information about the Current logic structure of database?

How this informations recorded in the DBMS and who is responsible to maintain?

Answer 1

To obtain information about the Current logic structure of database we have DATA MODELLING. Data modelling is the first step of designing the database. Following phases we describe in this:

• Data Phase : The data contained in the database (e.g., entities: students, courses,lecturer)
• Relationship Phase: The relationships between data items (e.g., students are supervised by lecturers; lecturers teach courses)
• Constraint Phase :The constraints on data (e.g., student number has exactly eight digits; a subject has four or six units of credit only)

The database design phase includes , how the data are represented using a certain data model. The data model is a collection of concepts or notations for describing data, data relationships, data semantics and data constraints. Most data models also include a set of basic operations for manipulating data in the database.

How this informations recorded in the DBMS ?

Information in database is stored in form of tables.

A database table is composed of records and fields that hold data. Tables are also called datasheets. Each table in a database holds data about a different, but related, subject. Data is stored in records. A record is composed of fields and contains all the data about one particular person, company, or item in a database. A field is part of a record and contains a single piece of data for the subject of the record. Example:- Subject_Id is the filed with 2 records. Fields appear as columns in a database table. Data from the Subject_Id field for two records.

Subject_Id	subject_name	Subject_teacher	Subject_Key
1	English	Mr. Kapoor	2K78
2	English	Mr.Khanna	2k78

Who is responsible to maintain?

The professionals who will handle the system will include marketing professionals, members of the IT team, database developers among others who should have enough knowledge about the said system and its functioning