what is primary key,unique key, foreign key? can u teach me
in simple language?
Answer Posted / heena verma
Primary Key:- it is a contraint(checks) provided by DBMS.
if we want to make a coumn unique and not null then the
column is defined as primary key. it is used to create
relations among the tables.
Is This Answer Correct ? | 55 Yes | 43 No |
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