estimate_selectivity.h File Reference

#include <string>

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Functions
double	EstimateSelectivity (THD *thd, Item *condition, const CompanionSet &companion_set, std::string *trace)
	For the given condition, to try estimate its filtering selectivity, on a 0..1 scale (where 1.0 lets all records through). More...

Function Documentation

EstimateSelectivity()

double EstimateSelectivity	(	THD *	thd,
		Item *	condition,
		const CompanionSet &	companion_set,
		std::string *	trace
	)

For the given condition, to try estimate its filtering selectivity, on a 0..1 scale (where 1.0 lets all records through).