MySQL 8.0.29
Source Code Documentation
estimate_selectivity.h
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22
23#ifndef SQL_JOIN_OPTIMIZER_ESTIMATE_SELECTIVITY
24#define SQL_JOIN_OPTIMIZER_ESTIMATE_SELECTIVITY
25
26#include <string>
27
28class THD;
29class Item;
30
31/**
32 For the given condition, to try estimate its filtering selectivity,
33 on a 0..1 scale (where 1.0 lets all records through).
34 */
35double EstimateSelectivity(THD *thd, Item *condition, std::string *trace);
36
37#endif // SQL_JOIN_OPTIMIZER_ESTIMATE_SELECTIVITY
Base class that is used to represent any kind of expression in a relational query.
Definition: item.h:802
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_class.h:945
double EstimateSelectivity(THD *thd, Item *condition, std::string *trace)
For the given condition, to try estimate its filtering selectivity, on a 0..1 scale (where 1....