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Merge 10.6 into 10.8

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This commit is contained in:
Marko Mäkelä
2023-05-11 09:00:27 +03:00
parent 7d44e2e7ff 7124911a2c
commit 1f1eaef0af
10 changed files with 277 additions and 156 deletions
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35
sql/sql_select.cc
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@@ -8526,25 +8526,26 @@ best_access_path(JOIN *join,
fanout= hash_join_fanout(join, s, remaining_tables, rnd_records,
hj_start_key, &stats_found);
join_sel= 1.0; // Don't do the "10% heuristic"
}
if (!stats_found)
{
/*
No OPTIMIZER_SWITCH_HASH_JOIN_CARDINALITY or no field statistics
found.
Take into account if there is non constant constraints used with
earlier tables in the where expression.
If yes, this will set fanout to rnd_records/4.
We estimate that there will be HASH_FANOUT (10%)
hash matches / row.
*/
if (found_constraint && !force_estimate)
rnd_records= use_found_constraint(rnd_records);
fanout= rnd_records;
join_sel= 0.1;
if (stats_found)
goto fanout_computed;
}
/*
No OPTIMIZER_SWITCH_HASH_JOIN_CARDINALITY or no field statistics
found.
Take into account if there is non constant constraints used with
earlier tables in the where expression.
If yes, this will set fanout to rnd_records/4.
We estimate that there will be HASH_FANOUT (10%)
hash matches / row.
*/
if (found_constraint && !force_estimate)
rnd_records= use_found_constraint(rnd_records);
fanout= rnd_records;
join_sel= 0.1;
fanout_computed:
tmp= s->quick ? s->quick->read_time : s->scan_time();
double cmp_time= (s->records - rnd_records)/TIME_FOR_COMPARE;
tmp= COST_ADD(tmp, cmp_time);