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| author | Marko Mäkelä <marko.makela@mariadb.com> | 2018-08-28 12:22:56 +0300 |
|---|---|---|
| committer | Marko Mäkelä <marko.makela@mariadb.com> | 2018-08-28 12:22:56 +0300 |
| commit | 7830fb7f45b3824c0375c00ae2cab357165904cf (patch) | |
| tree | 730521737fdc48e69f7650819e9a29da6487e1f4 /sql/multi_range_read.cc | |
| parent | b805ebd7ed49868f83e6fd3fe72a11ddacdce452 (diff) | |
| parent | 55163ba1bdb1a05daadc66c41c959994231b361c (diff) | |
| download | mariadb-git-7830fb7f45b3824c0375c00ae2cab357165904cf.tar.gz | |
Merge 10.2 into 10.3
Diffstat (limited to 'sql/multi_range_read.cc')
| -rw-r--r-- | sql/multi_range_read.cc | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/sql/multi_range_read.cc b/sql/multi_range_read.cc index cf587ef4acd..d6952e71899 100644 --- a/sql/multi_range_read.cc +++ b/sql/multi_range_read.cc @@ -18,6 +18,7 @@ #include <my_bit.h> #include "sql_select.h" #include "key.h" +#include "sql_statistics.h" /**************************************************************************** * Default MRR implementation (MRR to non-MRR converter) @@ -64,7 +65,12 @@ handler::multi_range_read_info_const(uint keyno, RANGE_SEQ_IF *seq, ha_rows rows, total_rows= 0; uint n_ranges=0; THD *thd= table->in_use; + uint limit= thd->variables.eq_range_index_dive_limit; + bool use_statistics_for_eq_range= eq_ranges_exceeds_limit(seq, + seq_init_param, + limit); + /* Default MRR implementation doesn't need buffer */ *bufsz= 0; @@ -88,8 +94,15 @@ handler::multi_range_read_info_const(uint keyno, RANGE_SEQ_IF *seq, min_endp= range.start_key.length? &range.start_key : NULL; max_endp= range.end_key.length? &range.end_key : NULL; } + int keyparts_used= my_count_bits(range.start_key.keypart_map); if ((range.range_flag & UNIQUE_RANGE) && !(range.range_flag & NULL_RANGE)) rows= 1; /* there can be at most one row */ + else if (use_statistics_for_eq_range && + !(range.range_flag & NULL_RANGE) && + (range.range_flag & EQ_RANGE) && + table->key_info[keyno].actual_rec_per_key(keyparts_used - 1) > 0.5) + rows= + (ha_rows) table->key_info[keyno].actual_rec_per_key(keyparts_used - 1); else { if (HA_POS_ERROR == (rows= this->records_in_range(keyno, min_endp, |