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Merge with 4.0.13

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monty@narttu.mysql.fi
2003-05-19 16:35:49 +03:00
parent 524878e935 fc0df599dc
commit dd2b7918cd
317 changed files with 6662 additions and 3466 deletions
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79
sql/opt_sum.cc
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@ -69,8 +69,10 @@ static int maxmin_in_range(bool max_fl, Field* field, COND *cond);
RETURN VALUES
0 No errors
1 if all items was resolved
-1 on impossible conditions
1 if all items were resolved
-1 on impossible conditions
OR an error number from my_base.h HA_ERR_... if a deadlock or a lock
wait timeout happens, for example
*/
int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
@ -82,6 +84,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
table_map where_tables= 0;
Item *item;
COND *org_conds= conds;
int error;
if (conds)
where_tables= conds->used_tables();
@ -131,7 +134,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
if (outer_tables || (table->table->file->table_flags() &
HA_NOT_EXACT_COUNT))
{
const_result= 0; // Can't optimize left join
const_result= 0; // Can't optimize left join
break;
}
tables->table->file->info(HA_STATUS_VARIABLE | HA_STATUS_NO_LOCK);
@ -164,6 +167,11 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
Item_field *item_field= ((Item_field*) expr);
TABLE *table= item_field->field->table;
if ((table->file->table_flags() & HA_NOT_READ_AFTER_KEY))
{
const_result=0;
break;
}
/*
Look for a partial key that can be used for optimization.
If we succeed, ref.key_length will contain the length of
@ -179,18 +187,21 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
const_result= 0;
break;
}
bool error= table->file->index_init((uint) ref.key);
error= table->file->index_init((uint) ref.key);
if (!ref.key_length)
error= table->file->index_first(table->record[0]) != 0;
error= table->file->index_first(table->record[0]);
else
error= table->file->index_read(table->record[0],key_buff,
ref.key_length,
range_fl & NEAR_MIN ?
HA_READ_AFTER_KEY :
HA_READ_KEY_OR_NEXT) ||
reckey_in_range(0, &ref, item_field->field,
conds, range_fl, prefix_len);
{
error= table->file->index_read(table->record[0],key_buff,
ref.key_length,
range_fl & NEAR_MIN ?
HA_READ_AFTER_KEY :
HA_READ_KEY_OR_NEXT);
if (!error && reckey_in_range(0, &ref, item_field->field,
conds, range_fl, prefix_len))
error= HA_ERR_KEY_NOT_FOUND;
}
if (table->key_read)
{
table->key_read= 0;
@ -198,10 +209,16 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
}
table->file->index_end();
if (error)
return -1; // No rows matching where
{
if (error == HA_ERR_KEY_NOT_FOUND || error == HA_ERR_END_OF_FILE)
return -1; // No rows matching WHERE
/* HA_ERR_LOCK_DEADLOCK or some other error */
table->file->print_error(error, MYF(0));
return(error);
}
removed_tables|= table->map;
}
else if (!expr->const_item()) // This is VERY seldom false
else if (!expr->const_item()) // This is VERY seldom false
{
const_result= 0;
break;
@ -249,18 +266,20 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
const_result= 0;
break;
}
bool error= table->file->index_init((uint) ref.key);
error= table->file->index_init((uint) ref.key);
if (!ref.key_length)
error=table->file->index_last(table->record[0]) != 0;
error= table->file->index_last(table->record[0]);
else
error= table->file->index_read(table->record[0], key_buff,
ref.key_length,
range_fl & NEAR_MAX ?
HA_READ_BEFORE_KEY :
HA_READ_PREFIX_LAST_OR_PREV) ||
reckey_in_range(1, &ref, item_field->field,
conds, range_fl, prefix_len);
{
error= table->file->index_read(table->record[0], key_buff,
ref.key_length,
range_fl & NEAR_MAX ?
HA_READ_BEFORE_KEY :
HA_READ_PREFIX_LAST_OR_PREV);
if (!error && reckey_in_range(1, &ref, item_field->field,
conds, range_fl, prefix_len))
error= HA_ERR_KEY_NOT_FOUND;
if (table->key_read)
{
table->key_read=0;
@ -268,10 +287,16 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
}
table->file->index_end();
if (error)
return -1; // Impossible query
{
if (error == HA_ERR_KEY_NOT_FOUND || error == HA_ERR_END_OF_FILE)
return -1; // No rows matching WHERE
/* HA_ERR_LOCK_DEADLOCK or some other error */
table->file->print_error(error, MYF(0));
return(error);
}
removed_tables|= table->map;
}
else if (!expr->const_item()) // This is VERY seldom false
else if (!expr->const_item()) // This is VERY seldom false
{
const_result= 0;
break;
@ -597,6 +622,10 @@ static bool matching_cond(bool max_fl, TABLE_REF *ref, KEY *keyinfo,
(if we have a condition field = const, prefix_len contains the length
of the whole search key)
NOTE
This function may set table->key_read to 1, which must be reset after
index is used! (This can only happen when function returns 1)
RETURN
0 Index can not be used to optimize MIN(field)/MAX(field)
1 Can use key to optimize MIN()/MAX()