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mirror of https://github.com/MariaDB/server.git synced 2025-07-29 05:21:33 +03:00
sql/mysql_priv.h:
  Auto merged
sql/sql_select.cc:
  Auto merged
This commit is contained in:
unknown
2004-04-08 23:50:10 +03:00
21 changed files with 1477 additions and 1307 deletions

View File

@ -3746,7 +3746,8 @@ make_join_readinfo(JOIN *join, uint options)
table->key_read=1;
table->file->extra(HA_EXTRA_KEYREAD);
}
else if (!table->used_keys.is_clear_all() && ! (tab->select && tab->select->quick))
else if (!table->used_keys.is_clear_all() &&
!(tab->select && tab->select->quick))
{ // Only read index tree
tab->index=find_shortest_key(table, & table->used_keys);
tab->table->file->index_init(tab->index);
@ -6907,6 +6908,7 @@ static int test_if_order_by_key(ORDER *order, TABLE *table, uint idx,
key_part_end=key_part+table->key_info[idx].key_parts;
key_part_map const_key_parts=table->const_key_parts[idx];
int reverse=0;
DBUG_ENTER("test_if_order_by_key");
for (; order ; order=order->next, const_key_parts>>=1)
{
@ -6917,25 +6919,24 @@ static int test_if_order_by_key(ORDER *order, TABLE *table, uint idx,
Skip key parts that are constants in the WHERE clause.
These are already skipped in the ORDER BY by const_expression_in_where()
*/
while (const_key_parts & 1)
{
key_part++; const_key_parts>>=1;
}
for (; const_key_parts & 1 ; const_key_parts>>= 1)
key_part++;
if (key_part == key_part_end || key_part->field != field)
return 0;
DBUG_RETURN(0);
/* set flag to 1 if we can use read-next on key, else to -1 */
flag=(order->asc == !(key_part->key_part_flag & HA_REVERSE_SORT))
? 1 : -1;
flag= ((order->asc == !(key_part->key_part_flag & HA_REVERSE_SORT)) ? 1 : -1);
if (reverse && flag != reverse)
return 0;
DBUG_RETURN(0);
reverse=flag; // Remember if reverse
key_part++;
}
*used_key_parts= (uint) (key_part - table->key_info[idx].key_part);
return reverse;
DBUG_RETURN(reverse);
}
static uint find_shortest_key(TABLE *table, const key_map *usable_keys)
{
uint min_length= (uint) ~0;
@ -6958,18 +6959,20 @@ static uint find_shortest_key(TABLE *table, const key_map *usable_keys)
}
/*
Test if a second key is the subkey of the first one.
SYNOPSIS
is_subkey()
key_part - first key parts
ref_key_part - second key parts
ref_key_part_end - last+1 part of the second key
DESCRIPTION
Test if a second key is the subkey of the first one.
key_part First key parts
ref_key_part Second key parts
ref_key_part_end Last+1 part of the second key
NOTE
Second key MUST be shorter than the first one.
RETURN
1 - is the subkey
0 - otherwise
1 is a subkey
0 no sub key
*/
inline bool
@ -6983,20 +6986,21 @@ is_subkey(KEY_PART_INFO *key_part, KEY_PART_INFO *ref_key_part,
}
/*
Test if we can use one of the 'usable_keys' instead of 'ref' key for sorting
SYNOPSIS
test_if_subkey()
ref - number of key, used for WHERE clause
usable_keys - keys for testing
DESCRIPTION
Test if we can use one of the 'usable_keys' instead of 'ref' key.
ref Number of key, used for WHERE clause
usable_keys Keys for testing
RETURN
MAX_KEY - if we can't use other key
the number of found key - otherwise
MAX_KEY If we can't use other key
the number of found key Otherwise
*/
static uint
test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts,
const key_map& usable_keys)
const key_map *usable_keys)
{
uint nr;
uint min_length= (uint) ~0;
@ -7007,7 +7011,7 @@ test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts,
for (nr= 0 ; nr < table->keys ; nr++)
{
if (usable_keys.is_set(nr) &&
if (usable_keys->is_set(nr) &&
table->key_info[nr].key_length < min_length &&
table->key_info[nr].key_parts >= ref_key_parts &&
is_subkey(table->key_info[nr].key_part, ref_key_part,
@ -7051,12 +7055,12 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
if ((*tmp_order->item)->type() != Item::FIELD_ITEM)
{
usable_keys.clear_all();
break;
DBUG_RETURN(0);
}
usable_keys.intersect(
((Item_field*) (*tmp_order->item))->field->part_of_sortkey);
usable_keys.intersect(((Item_field*) (*tmp_order->item))->
field->part_of_sortkey);
if (usable_keys.is_clear_all())
break; // No usable keys
DBUG_RETURN(0); // No usable keys
}
ref_key= -1;
@ -7092,9 +7096,9 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
keys
*/
if (table->used_keys.is_set(ref_key))
usable_keys.merge(table->used_keys);
usable_keys.intersect(table->used_keys);
if ((new_ref_key= test_if_subkey(order, table, ref_key, ref_key_parts,
usable_keys)) < MAX_KEY)
&usable_keys)) < MAX_KEY)
{
/* Found key that can be used to retrieve data in sorted order */
if (tab->ref.key >= 0)
@ -7154,6 +7158,8 @@ test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order,ha_rows select_limit,
/* fall through */
}
}
else if (select && select->quick)
select->quick->sorted= 1;
DBUG_RETURN(1); /* No need to sort */
}
}
@ -7292,9 +7298,9 @@ create_sort_index(THD *thd, JOIN *join, ORDER *order,
For impossible ranges (like when doing a lookup on NULL on a NOT NULL
field, quick will contain an empty record set.
*/
if (!(select->quick= tab->type == JT_FT ?
new FT_SELECT(thd, table, tab->ref.key) :
get_quick_select_for_ref(thd, table, &tab->ref)))
if (!(select->quick= (tab->type == JT_FT ?
new FT_SELECT(thd, table, tab->ref.key) :
get_quick_select_for_ref(thd, table, &tab->ref))))
goto err;
}
}