What is primary key short answer?
- What is primary key class 8 short answer?
- Why is a primary key?
- What is primary key IT Class 10?
- What is primary key 11th class?
What is primary key class 8 short answer?
Answer: Primary key is a field that uniquely identifies each record in a table. For example, in a school database, the Roll Number of each student uniquely identifies each student. A Primary key does not allow Null Values and must always have a unique value.
Why is a primary key?
The main purpose of primary key is to identify the uniqueness of a row, where as unique key is to prevent the duplicates, following are the main difference between primary key and unique key. Primary Key : There can only be one primary key for a table. The primary key consists of one or more columns.
What is primary key IT Class 10?
Answer: A field which uniquely identifies each record in a table is known as primary key.
What is primary key 11th class?
Primary Key: A candidate key that is primarily chosen for unique identification of tuples in a Relation. Any subset of Primary key should not be Primary key. Alternate Key: Candidate keys that not chosen as primary key are the alternate keys. Example: In a LIBRARY Table.
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