COMPUTER SCIENCE AND ENGINEERING
SQL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Used to identify a column
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Alias for foreign key
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Alias for primary key
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Used to uniquely identify a row
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Detailed explanation-1: -Primary key, on the other hand, is the Candidate key chosen to uniquely identify rows in a database table.
Detailed explanation-2: -A characteristic or group of attributes that can uniquely identify a tuple is known as a candidate key in MySQL Keys.
Detailed explanation-3: -Candidate key is also a unique key to identify a record uniquely in a table. 2. Primary key column value cannot be NULL. Candidate key column can have NULL value.
Detailed explanation-4: -The primary key is used to identify a specific row in a table. The unique key is used to ensure that there is only one entry in a specific table.
Detailed explanation-5: -A candidate key SQL is a column or a set of columns that can qualify as a primary key in the database. There can be multiple SQL candidate keys in a database relation and each candidate can work as a primary key for the table.