Summary of BCNF Decomposition
Find a dependency that violates the BCNF
condition:
A , A , … A
1
2
n
B , B , … B
1
2
m
A’s
Others
B’s
R1
R2
Heuristics: choose B , B , … B “as
large as possible”
1
2
m
Decompose:
Is there a
2-attribute
relation that is
not in BCNF ?
Continue
until
there
are no
BCNF
violations
left.