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Merge.

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This commit is contained in:
Igor Babaev
2014-03-19 14:58:29 -07:00
parent a60f227c04 06ef0bdad2
commit d51ee6d412
6 changed files with 257 additions and 40 deletions
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38
sql/sql_select.cc
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@ -5556,9 +5556,23 @@ void set_position(JOIN *join,uint idx,JOIN_TAB *table,KEYUSE *key)
/* Estimate of the number matching candidates in the joined table */
inline
ha_rows matching_candidates_in_table(JOIN_TAB *s, bool with_found_constraint)
double matching_candidates_in_table(JOIN_TAB *s, bool with_found_constraint,
uint use_cond_selectivity)
{
ha_rows records= s->found_records;
ha_rows records;
double dbl_records;
if (use_cond_selectivity > 1)
{
TABLE *table= s->table;
double sel= table->cond_selectivity;
double table_records= table->stat_records();
dbl_records= table_records * sel;
return dbl_records;
}
records = s->found_records;
/*
If there is a filtering condition on the table (i.e. ref analyzer found
at least one "table.keyXpartY= exprZ", where exprZ refers only to tables
@ -5578,7 +5592,8 @@ ha_rows matching_candidates_in_table(JOIN_TAB *s, bool with_found_constraint)
if (s->table->quick_condition_rows != s->found_records)
records= s->table->quick_condition_rows;
return records;
dbl_records= records;
return dbl_records;
}
@ -5621,6 +5636,7 @@ best_access_path(JOIN *join,
POSITION *loose_scan_pos)
{
THD *thd= join->thd;
uint use_cond_selectivity= thd->variables.optimizer_use_condition_selectivity;
KEYUSE *best_key= 0;
uint best_max_key_part= 0;
my_bool found_constraint= 0;
@ -6052,7 +6068,8 @@ best_access_path(JOIN *join,
{
double join_sel= 0.1;
/* Estimate the cost of the hash join access to the table */
ha_rows rnd_records= matching_candidates_in_table(s, found_constraint);
double rnd_records= matching_candidates_in_table(s, found_constraint,
use_cond_selectivity);
tmp= s->quick ? s->quick->read_time : s->scan_time();
tmp+= (s->records - rnd_records)/(double) TIME_FOR_COMPARE;
@ -6064,7 +6081,7 @@ best_access_path(JOIN *join,
best_time= tmp +
(record_count*join_sel) / TIME_FOR_COMPARE * rnd_records;
best= tmp;
records= rows2double(rnd_records);
records= rnd_records;
best_key= hj_start_key;
best_ref_depends_map= 0;
best_uses_jbuf= TRUE;
@ -6111,7 +6128,8 @@ best_access_path(JOIN *join,
!(s->table->force_index && best_key && !s->quick) && // (4)
!(best_key && s->table->pos_in_table_list->jtbm_subselect)) // (5)
{ // Check full join
ha_rows rnd_records= matching_candidates_in_table(s, found_constraint);
double rnd_records= matching_candidates_in_table(s, found_constraint,
use_cond_selectivity);
/*
Range optimizer never proposes a RANGE if it isn't better
@ -6184,7 +6202,7 @@ best_access_path(JOIN *join,
will ensure that this will be used
*/
best= tmp;
records= rows2double(rnd_records);
records= rnd_records;
best_key= 0;
/* range/index_merge/ALL/index access method are "independent", so: */
best_ref_depends_map= 0;
@ -7289,6 +7307,10 @@ double table_cond_selectivity(JOIN *join, uint idx, JOIN_TAB *s,
keyuse++;
} while (keyuse->table == table && keyuse->key == key);
}
else
{
sel= 1;
}
/*
If the field f from the table is equal to a field from one the
@ -8313,7 +8335,7 @@ get_best_combination(JOIN *join)
Save records_read in JOIN_TAB so that select_describe()/etc don't have
to access join->best_positions[].
*/
j->records_read= (ha_rows)join->best_positions[tablenr].records_read;
j->records_read= join->best_positions[tablenr].records_read;
j->cond_selectivity= join->best_positions[tablenr].cond_selectivity;
join->map2table[j->table->tablenr]= j;