6
Conjunctive Queries
•
Have the form:
9
x
1
…
9
x
k
.(C
1
Æ
…
Æ
C
m
)
•
•
Where each C
i
is R(…) or x
i
=x
j
or x
i
¹
x
j
Empolyee(x,Seattle,-),Employee(x,y,Clerk),Employee(-,y,Lawer)
