what is the difference between primary key & foreign key?
Answers were Sorted based on User's Feedback
Answer / gajendra jain
A table can have only one Primery key but it can have any number of Foreign key.
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / anand
Primary key is used to identify a row in a table and it
doesnot allow null values. It avoids duplication of rows.
whereas foreign key refers to a column or combination of
columns included in the defenition of referential integrity
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / abhishek ranjan
The main diference between primary key and the foreign key is that the primary key is a column or a set of columns that can be used to uniquely identify a row in a table while the foreign key is a column or a set of columns that refer to a primary key or a candidate key of another table. Foreign key mainly provides a method to link information in several tables. Another difference is that a table can have a single primary key, but it can have multiple foreign keys that can reference different tables.
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / leang heng
Primary Key is a column or group of columns that determine
in each Record to make not null.
Foreign Key is Column that provide Relationship to Primary
Key between Entities or Table.
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / praneeth
primary key helps in uniquely identifying the records in a table
a foreign key is a field that points to the primary key of another table which links one table to another table
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / aarti
Primary Key : It is a unique key of the table.Unique for
each record in the table(e.g ID).
Foreign Key : When a primary key is used as a reference key
in another table then it is called as a foreign key.It is
used to link two tables.
Is This Answer Correct ? | 1 Yes | 2 No |
Answer / keyman
Foreign key = Florida Keys (Keys in a foreign land)
Primary Key = The main key you use to enter you home
Is This Answer Correct ? | 12 Yes | 36 No |
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