difference between primary key and unique key

difference between primary key and unique key

mysql sql database primary-key unique-key

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INSERT ... ON DUPLICATE KEY (do nothing)

mysql sql unique-key

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How to remove unique key from mysql table

mysql sql unique-key

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make text column as unique key

mysql sql database unique-key

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SQL - Unique Key, Primary Key & Foreign Key

sql foreign-keys primary-key rdbms unique-key

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