Relational Algebra
Procedured Query Language
- It uses Operators to perform Queries.
Relational Operations:
1)Select Operation:
The Select Operation selects tuples that satisfy a given
predigate. It is denoted by ‘σ’ Sigma p(r). Where σ is used for
selection projection and ‘r’ is used for Relational and ‘p’ is a
Propositional logic which use connectors like AND, OR, NOT
and Relational Operators like >,<,>=,=< Assignment Operator
like = and ≠ Operator.
Branch_name Loan no Amt
Itahari 101 20,000
Dharan 102 10,000
BRT 103 30,000
BRT 105 50,000
σ Branch_name = “BRT”(Loan)
Branch_name Loan no Amt
BRT 103 30,000
BRT 105 50,000
2) Project Operation:
This operation shows the list of those attributes that
It is denoted by Pie ‘π’. (π a1, a2)
Name Dept City
Anish IT BRT
Manish Officer KTM
Sanish Police BRT
