Which of the following year the concept of database was introduced?
a) 1950
b) 1955
c) 1960
d) 1965
How many types of database models?
a) one
b) two
c) three
d) four
Explanation: Network model, Hierarchical model
Who proposed relational model for database in landmark paper in 1972?
a) E. F Codd
b) P. Chen
c) John
d) none of these
Who proposed entity relationship model for database?
a) E. F Codd
b) P. Chen
c) John
d) none of these
Which of the following year P. Chen developed entity relationship model for database?
a) 1975
b) 1976
c) 1977
d) 1978
Wat does ER stand for in database?
a) early relation
b) entity relationship
c) employ relation
d) enlarge relationship
