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Database training
1.2.06. Select operation
SELECT a subset of tuples from a relation
Uses selection condition
Evaluate each tuple to true of false
False tuples discarded
Sigma (
s
)
output =
s
(cond)
(input_relation)
Relation schema: R(output) = R(input_relation)
Commutative
‹ 1.2.05. Basic algebra
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1.2.07. Project operation ›
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