What are the general transformation rules, Database Management System

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What are the General Transformation Rules for Relational operations?

Ans: The transformation rules transform one relational algebra expression to AN

EQUIVALENT ONE

1. Employed by the query optimizer to optimize query tree

2. Any type of rule, if applied, ensures that the resultant tree is equivalent → resulting execution plan is equivalent

General Transformation Rules is as follow:

1. Commutativity of s: The s operation is commutative:

s_c1 (s_c2(R)) = s_c2(s_c1(R))
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