What are primary keys and foreign keys?
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Answer / nevual
Primary keys are the unique identifiers for each row. They
must contain unique values and cannot be null. Due to their
importance in relational databases, Primary keys are the
most fundamental of all keys and constraints. A table can
have only one Primary key.
Foreign keys are both a method of ensuring data integrity
and a manifestation of the relationship between tables.
| Is This Answer Correct ? | 7 Yes | 0 No |
Answer / sudarsan
Primary key is a unique id for each table. This prevents
duplication of records. Each table can have a single
primary key. They can be refrenced by any tables as a
foreign key.
| Is This Answer Correct ? | 4 Yes | 0 No |
Answer / jai prakash chauhan
Primary keys are by default clustered index.
| Is This Answer Correct ? | 3 Yes | 2 No |
• Primary Key: A unique identifier for a table’s record (e.g., id in a table).
• Foreign Key: A column in a table that refers to the primary key of another table, establishing a relationship between tables.
| Is This Answer Correct ? | 0 Yes | 0 No |
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