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MDEV-6434: Wrong result (extra rows) with ORDER BY, multiple-column index, InnoDB

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- Filesort has an optmization where it reads only columns that are 
  needed before the sorting is done.
- When ref(_or_null) is picked by the join optimizer, it may remove parts
  of WHERE clause that are guaranteed to be true.
- However, if we use quick select, we must put all of the range columns into the 
  read set. Not doing so will may cause us to fail to detect the end of the range.
This commit is contained in:
Sergey Petrunya
2014-07-22 15:52:49 +04:00
parent 71a596b90c
commit 07c0b1d8d0
5 changed files with 110 additions and 1 deletions
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57
sql/opt_range.cc
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@@ -10538,6 +10538,7 @@ QUICK_RANGE_SELECT *get_quick_select_for_ref(THD *thd, TABLE *table,
if (quick->init())
goto err;
quick->records= records;
quick->max_used_key_length= ref->key_parts;
if ((cp_buffer_from_ref(thd, table, ref) && thd->is_fatal_error) ||
!(range= new(alloc) QUICK_RANGE()))
@@ -10547,7 +10548,7 @@ QUICK_RANGE_SELECT *get_quick_select_for_ref(THD *thd, TABLE *table,
range->min_length= range->max_length= ref->key_length;
range->min_keypart_map= range->max_keypart_map=
make_prev_keypart_map(ref->key_parts);
range->flag= (ref->key_length == key_info->key_length ? EQ_RANGE : 0);
range->flag= EQ_RANGE;
if (!(quick->key_parts=key_part=(KEY_PART *)
alloc_root(&quick->alloc,sizeof(KEY_PART)*ref->key_parts)))
@@ -11756,6 +11757,60 @@ void QUICK_ROR_UNION_SELECT::add_keys_and_lengths(String *key_names,
}
void QUICK_RANGE_SELECT::add_used_key_part_to_set(MY_BITMAP *col_set)
{
for (uint i=0; i < max_used_key_length; i++)
{
bitmap_set_bit(col_set, key_parts[i].field->field_index);
}
}
void QUICK_GROUP_MIN_MAX_SELECT::add_used_key_part_to_set(MY_BITMAP *col_set)
{
for (uint i=0; i < max_used_key_length; i++)
{
bitmap_set_bit(col_set, index_info->key_part[i].field->field_index);
}
}
void QUICK_ROR_INTERSECT_SELECT::add_used_key_part_to_set(MY_BITMAP *col_set)
{
List_iterator_fast<QUICK_SELECT_WITH_RECORD> it(quick_selects);
QUICK_SELECT_WITH_RECORD *quick;
while ((quick= it++))
{
quick->quick->add_used_key_part_to_set(col_set);
}
}
void QUICK_INDEX_SORT_SELECT::add_used_key_part_to_set(MY_BITMAP *col_set)
{
QUICK_RANGE_SELECT *quick;
List_iterator_fast<QUICK_RANGE_SELECT> it(quick_selects);
while ((quick= it++))
{
quick->add_used_key_part_to_set(col_set);
}
if (pk_quick_select)
pk_quick_select->add_used_key_part_to_set(col_set);
}
void QUICK_ROR_UNION_SELECT::add_used_key_part_to_set(MY_BITMAP *col_set)
{
QUICK_SELECT_I *quick;
List_iterator_fast<QUICK_SELECT_I> it(quick_selects);
while ((quick= it++))
{
quick->add_used_key_part_to_set(col_set);
}
}
/*******************************************************************************
* Implementation of QUICK_GROUP_MIN_MAX_SELECT
*******************************************************************************/