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GATE 2021 · Set-1
Database ManagementmediumNAT1 mark
A relation \(r(A,B)\) in a relational database has \(1200\) tuples. Attribute \(A\) has integer values from \(6\) to \(20\), and attribute \(B\) has integer values from \(1\) to \(20\). Assume that \(A\) and \(B\) are independently distributed. The estimated number of tuples in the output of \(\sigma_{(A>10)\lor(B=18)}(r)\) is ______.
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