In mysql, the primary key constraint is used to uniquely identify each record in a table.primary key contains unique values only and the column defined as primary key column can not be null. a table ...

In MySQL, the PRIMARY KEY constraint is used to uniquely identify each record in a table. Primary key contains UNIQUE values only and the column defined as Primary key column can not be NULL. A table ...

MySQL table primary keys and unique indexes prevent multiple rows with the same index from being added to the table. If you try to insert a duplicate row with a standard INSERT statement, you will ...