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MDEV-15306: Wrong/Unexpected result with the value optimizer_use_condition_selectivity set to 4

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Currently for selectivity calculation we perform range analysis for a column even when we don't have any statistics(EITS).
This makes less sense but is used to catch contradiction for WHERE condition.

So the solution is to not perform range analysis for selectivity calculation for columns that do not have statistics.
This commit is contained in:
Varun Gupta
2018-08-28 21:59:11 +05:30
parent 5fb251642e
commit a9c09c95bd
5 changed files with 152 additions and 11 deletions
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29
sql/sql_statistics.h
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@ -342,12 +342,17 @@ private:
public:
Histogram histogram;
uint32 no_values_provided_bitmap()
{
return
((1 << (COLUMN_STAT_HISTOGRAM-COLUMN_STAT_COLUMN_NAME))-1) <<
(COLUMN_STAT_COLUMN_NAME+1);
}
void set_all_nulls()
{
column_stat_nulls=
((1 << (COLUMN_STAT_HISTOGRAM-COLUMN_STAT_COLUMN_NAME))-1) <<
(COLUMN_STAT_COLUMN_NAME+1);
column_stat_nulls= no_values_provided_bitmap();
}
void set_not_null(uint stat_field_no)
@ -393,8 +398,22 @@ public:
bool min_max_values_are_provided()
{
return !is_null(COLUMN_STAT_MIN_VALUE) &&
!is_null(COLUMN_STAT_MIN_VALUE);
}
!is_null(COLUMN_STAT_MAX_VALUE);
}
/*
This function checks whether the values for the fields of the statistical
tables that were NULL by DEFAULT for a column have changed or not.
@retval
TRUE: Statistics are not present for a column
FALSE: Statisitics are present for a column
*/
bool no_stat_values_provided()
{
if (column_stat_nulls == no_values_provided_bitmap())
return true;
return false;
}
};