rdbms - Why use primary keys? -


Identifying a unique column in the table uses a different primary key? Can not this be done on one column only using an autoimmune block? I understand that PK and FK are used to relate to different tables, but can it be done only by joining?

> For the integrity referenced with most foreign keys, when you have a PK, it will also create an indicator behind the scenes and in this way you do not need a table scan in search of values ​​


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