1.   The relational algebra is a procedural language.

2.   As we shall see, the relational calculus is less procedural, and the database system is expected to translate this into the procedural steps of the relational algebra.

3.   We now look at the relational algebra and the relational calculus in more detail.

4.   The relational algebra is a collection of operators on relations.

5.   The other basic operations in the relational algebra are not traditional set operators.

6.   In using the relational algebra.

7.   The relational algebra is fairly simple and powerful.

8.   When compared to the relational algebra, the relational calculus is more oriented towards expressing the user requests in a way that the user may construct.

a. + algebra >>共 29
relational 27.50%
abstract 5.00%
accelerated 2.50%
advanced 2.50%
agreed 2.50%
american 2.50%
basic 2.50%
battered 2.50%
different 2.50%
difficult 2.50%
relational + n. >>共 27
database 57.25%
model 11.59%
algebra 7.97%
calculus 3.62%
aggression 1.45%
approach 1.45%
information 1.45%
term 1.45%
architecture 0.72%
aspect 0.72%
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