<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
domain	B-Application
relational	I-Application
calculus	I-Application
(	O
DRC	O
)	O
is	O
a	O
calculus	O
that	O
was	O
introduced	O
by	O
Michel	O
Lacroix	O
and	O
Alain	O
Pirotte	O
as	O
a	O
declarative	B-Language
database	B-Language
query	I-Language
language	I-Language
for	O
the	O
relational	B-Architecture
data	I-Architecture
model	I-Architecture
.	O
</s>
<s>
This	O
language	O
uses	O
the	O
same	O
operators	O
as	O
tuple	B-Application
calculus	I-Application
,	O
</s>
<s>
The	O
existential	B-Algorithm
quantifier	I-Algorithm
( ∃	O
)	O
and	O
the	O
universal	O
quantifier	O
( ∀	O
)	O
can	O
be	O
used	O
to	O
bind	O
the	O
variables	O
.	O
</s>
<s>
Its	O
computational	O
expressiveness	O
is	O
equivalent	O
to	O
that	O
of	O
relational	B-Algorithm
algebra	I-Algorithm
.	O
</s>
