Do I need to mention primary key for each table

+1 vote
Hey,

I am bit confused about primary key and constraints in database. Is there any rule that for each table I need to use primary key or foreign key?
Jul 4, 2019 in Database by Pritha
643 views

1 answer to this question.

+1 vote

Hi Pritha,

First, there is no hard and fast rule to add constraint in your table But we use constraint in our table to reduce data repetition and redundancy in our table.

And if you want to fetch one particular data that time primary key will help you to get that row only.

I hope, this will help you out

Thank you,

answered Jul 4, 2019 by sampriti
• 1,120 points

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