For a database relation $R(a, b, c, d)$, where the domains $a, b, c, d$ include only atomic values, only the following functional dependencies and those that can be inferred from them hold
This relation is
in first normal form but not in second normal form
in second normal form but not in first normal form
in third normal form
none of the above
by using decomposition in ac bd ab
what is means?
for 3,AB---->B(KEY---->PRIME ATTRIBUTE)ALLOWED IN 2NF
AB---->DE NO PARTIAL DEPENDENCY
@set2018 When A defines everything then A is the PK and AB is a superkey.
3rd FD is needless, there is no parital dependency. You defined the wrong primary key initially.