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MDEV-22851: Engine independent index statistics are incorrect for large tables on Windows

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An oveflow was happening on windows because on Windows sizeof(ulong) is 4 bytes
while it is 8 bytes on Linux.
Switched avg_frequency and avg length for column statistics to ulonglong.
Switched avg_frequency for index statistics to ulonglong.
This commit is contained in:
Varun Gupta
2020-07-14 12:09:10 +05:30
parent 67a03b7c94
commit dfdfeecb03
4 changed files with 67 additions and 15 deletions
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18
sql/sql_statistics.h
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@ -279,7 +279,9 @@ public:
uchar *min_max_record_buffers; /* Record buffers for min/max values */
Column_statistics *column_stats; /* Array of statistical data for columns */
Index_statistics *index_stats; /* Array of statistical data for indexes */
ulong *idx_avg_frequency; /* Array of records per key for index prefixes */
/* Array of records per key for index prefixes */
ulonglong *idx_avg_frequency;
uchar *histograms; /* Sequence of histograms */
};
@ -331,7 +333,7 @@ private:
CHAR values are stripped of trailing spaces.
Flexible values are stripped of their length prefixes.
*/
ulong avg_length;
ulonglong avg_length;
/*
The ratio N/D multiplied by the scale factor Scale_factor_avg_frequency,
@ -339,7 +341,7 @@ private:
N is the number of rows with not null value in the column,
D the number of distinct values among them
*/
ulong avg_frequency;
ulonglong avg_frequency;
public:
@ -389,12 +391,12 @@ public:
void set_avg_length (double val)
{
avg_length= (ulong) (val * Scale_factor_avg_length);
avg_length= (ulonglong) (val * Scale_factor_avg_length);
}
void set_avg_frequency (double val)
{
avg_frequency= (ulong) (val * Scale_factor_avg_frequency);
avg_frequency= (ulonglong) (val * Scale_factor_avg_frequency);
}
bool min_max_values_are_provided()
@ -433,11 +435,11 @@ private:
in the first k components, and D is the number of distinct
k-component prefixes among them
*/
ulong *avg_frequency;
ulonglong *avg_frequency;
public:
void init_avg_frequency(ulong *ptr) { avg_frequency= ptr; }
void init_avg_frequency(ulonglong *ptr) { avg_frequency= ptr; }
bool avg_frequency_is_inited() { return avg_frequency != NULL; }
@ -448,7 +450,7 @@ public:
void set_avg_frequency(uint i, double val)
{
avg_frequency[i]= (ulong) (val * Scale_factor_avg_frequency);
avg_frequency[i]= (ulonglong) (val * Scale_factor_avg_frequency);
}
};