diff options
Diffstat (limited to 'sql/sql_statistics.h')
| -rw-r--r-- | sql/sql_statistics.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/sql/sql_statistics.h b/sql/sql_statistics.h index 20ecf06bfee..35b3aa33acc 100644 --- a/sql/sql_statistics.h +++ b/sql/sql_statistics.h @@ -239,6 +239,17 @@ public: bool is_available() { return get_size() > 0 && get_values(); } + /* + This function checks that histograms should be usable only when + 1) the level of optimizer_use_condition_selectivity > 3 + 2) histograms have been collected + */ + bool is_usable(THD *thd) + { + return thd->variables.optimizer_use_condition_selectivity > 3 && + is_available(); + } + void set_value(uint i, double val) { switch (type) { |