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MDEV-4345

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Sampling of selectivity of LIKE predicate.
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unknown
2013-04-18 22:22:04 +03:00
parent 8c71e7a383
commit 9441e53653
16 changed files with 464 additions and 7 deletions
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7
sql/opt_range.h
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@ -1051,4 +1051,11 @@ void store_key_image_to_rec(Field *field, uchar *ptr, uint len);
extern String null_string;
/* check this number of rows (default value) */
#define SELECTIVITY_SAMPLING_LIMIT 5000
/* but no more then this part of table (10%) */
#define SELECTIVITY_SAMPLING_SHARE 0.10
/* do not check if we are going check less then this number of records */
#define SELECTIVITY_SAMPLING_THRESHOLD 10
#endif