what is primary key,unique key, foreign key? can u teach me
in simple language?
Answer Posted / vinodkumar
Primary key:it is a key in which uniquely identify the
answer which is stored in the DBMS.A table contains a
primary key.
Foreign key:A key used in the table to represent the primary
key i.e when the primary key is used in a table of one topic
then the same name can be used as foreign key in another topic
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