A note on estimating the cardinality of the projection of a database relation
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The paper by Ahad et al. [1] derives an analytical expression to estimate the cardinality of the projection of a database relation. In this note, we propose to show that this expression is in error even when all the parameters are assumed to be constant. We derive the correct formula for this expression.
[1] Dennis McLeod,et al. On estimating the cardinality of the projection of a database relation , 1989, TODS.