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Fixed a cost estimation bug introduced into in the function best_access_path

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of the 5.3 code line after a merge with 5.2 on 2010-10-28
in order not to allow the cost to access a joined table to be equal
to 0 ever.

Expanded data sets for many test cases to get the same execution plans
as before.
This commit is contained in:
Igor Babaev
2011-09-30 18:55:02 -07:00
parent 42b928ca05
commit 715dc5f99d
61 changed files with 703 additions and 217 deletions
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5
sql/sql_select.cc
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@ -5177,7 +5177,7 @@ best_access_path(JOIN *join,
tmp= table->file->keyread_time(key, 1, (ha_rows) tmp);
else
tmp= table->file->read_time(key, 1,
(ha_rows) min(tmp,s->worst_seeks)-1);
(ha_rows) min(tmp,s->worst_seeks));
tmp*= record_count;
}
}
@ -5341,13 +5341,14 @@ best_access_path(JOIN *join,
tmp= table->file->keyread_time(key, 1, (ha_rows) tmp);
else
tmp= table->file->read_time(key, 1,
(ha_rows) min(tmp,s->worst_seeks)-1);
(ha_rows) min(tmp,s->worst_seeks));
tmp*= record_count;
}
else
tmp= best_time; // Do nothing
}
DBUG_ASSERT(tmp > 0 || record_count == 0);
tmp += s->startup_cost;
loose_scan_opt.check_ref_access_part2(key, start_key, records, tmp);
} /* not ft_key */