Into the data: Day 8

Into the data: Day 8

On Day 8, I learned about relational databases and I learned about primary keys, foreign keys and composite key. A primary key is something that has unique value and can only appear once in that particular column.

As for a foreign key, it is that same primary key that appears in a different column where it is not the primary key and finally for the composite key, it is a mix of primary keys resulting in a unique key.

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Road to dev

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Chanak Karki

Chanak Karki

Road to dev

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