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IS 230 (Relational Algebra) - Dr. Yousry Taha . 2. Basic Relational Algebra Operations. A data model must include a set of operations to manipulate the data.A basic set of relational model operations constitute the Relational Algebra.These operations enable
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1. The Relational Algebra Dr. Yousry Taha
IS230
(This is the instructors notes and student has to read the textbook for complete material.)
2. IS 230 (Relational Algebra) - Dr. Yousry Taha 2 Basic Relational Algebra Operations A data model must include a set of operations to manipulate the data.
A basic set of relational model operations constitute the Relational Algebra.
These operations enable the user to specify basic retrieval requests which is also a relation.
A relational algebra expression is a sequence of relational algebra operations.
3. IS 230 (Relational Algebra) - Dr. Yousry Taha 3 Basic Relational Algebra Operations (cont) The relational algebra operations are divided into two groups: Set operations (?, n , , ? ) Operations developed specifically for the relational DB (Select (?) , Project (P), Join ( ) and others). Some additional operations were suggested to perform some common DB requests (aggregations (?), .).