Ace Test series: Database - Database Normalization

Question

Comments

1st is false b/c transitive dependency not allow in BcNF

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Please explain it little bit more @ashwin sir @anu sir

If Every non prime attributes are fully functionally dependent on every key then it will be in 2NF. or you can say in 3NF non prime attributes are fully functionally dependent on some key of R.

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please, check this one also @anu sir @ ashwin sir

https://gateoverflow.in/156664/ace-test-series-data 

Answer 1

1) false .......> it is true for 3NF.

2)false

3)true............>Unique key constraints are used to ensure that data is not duplicated in two rows in the database. One row in the database is allowed to have null for the value of the unique key constraint. 

Comments

didn’t understand your third point??

Answer 2

2 statements are wrong..1 and 3..

A unique key may be candidate key as well that can not be null...

Comments

so the two statements that are false are statement 1 and statement 3?

Please explain