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Merge neptunus.(none):/home/msvensson/mysql/mysql-5.0

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into  neptunus.(none):/home/msvensson/mysql/mysql-5.0-maint
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msvensson@neptunus.(none)
2007-02-06 14:45:08 +01:00
parent 47ae650a57 b444566412
commit ede3afe470
72 changed files with 2259 additions and 4498 deletions
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60
sql/sql_select.cc
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@ -707,11 +707,20 @@ JOIN::optimize()
{
int res;
/*
opt_sum_query() returns -1 if no rows match to the WHERE conditions,
or 1 if all items were resolved, or 0, or an error number HA_ERR_...
opt_sum_query() returns HA_ERR_KEY_NOT_FOUND if no rows match
to the WHERE conditions,
or 1 if all items were resolved,
or 0, or an error number HA_ERR_...
*/
if ((res=opt_sum_query(select_lex->leaf_tables, all_fields, conds)))
{
if (res == HA_ERR_KEY_NOT_FOUND)
{
DBUG_PRINT("info",("No matching min/max row"));
zero_result_cause= "No matching min/max row";
error=0;
DBUG_RETURN(0);
}
if (res > 1)
{
thd->fatal_error();
@ -719,13 +728,6 @@ JOIN::optimize()
DBUG_PRINT("error",("Error from opt_sum_query"));
DBUG_RETURN(1);
}
if (res < 0)
{
DBUG_PRINT("info",("No matching min/max row"));
zero_result_cause= "No matching min/max row";
error=0;
DBUG_RETURN(0);
}
DBUG_PRINT("info",("Select tables optimized away"));
zero_result_cause= "Select tables optimized away";
tables_list= 0; // All tables resolved
@ -855,6 +857,13 @@ JOIN::optimize()
{
ORDER *org_order= order;
order=remove_const(this, order,conds,1, &simple_order);
if (thd->net.report_error)
{
error= 1;
DBUG_PRINT("error",("Error from remove_const"));
DBUG_RETURN(1);
}
/*
If we are using ORDER BY NULL or ORDER BY const_expression,
return result in any order (even if we are using a GROUP BY)
@ -864,10 +873,11 @@ JOIN::optimize()
}
/*
Check if we can optimize away GROUP BY/DISTINCT.
We can do that if there are no aggregate functions and the
We can do that if there are no aggregate functions, the
fields in DISTINCT clause (if present) and/or columns in GROUP BY
(if present) contain direct references to all key parts of
an unique index (in whatever order).
an unique index (in whatever order) and if the key parts of the
unique index cannot contain NULLs.
Note that the unique keys for DISTINCT and GROUP BY should not
be the same (as long as they are unique).
@ -962,6 +972,12 @@ JOIN::optimize()
group_list= remove_const(this, (old_group_list= group_list), conds,
rollup.state == ROLLUP::STATE_NONE,
&simple_group);
if (thd->net.report_error)
{
error= 1;
DBUG_PRINT("error",("Error from remove_const"));
DBUG_RETURN(1);
}
if (old_group_list && !group_list)
select_distinct= 0;
}
@ -978,6 +994,12 @@ JOIN::optimize()
{
group_list= procedure->group= remove_const(this, procedure->group, conds,
1, &simple_group);
if (thd->net.report_error)
{
error= 1;
DBUG_PRINT("error",("Error from remove_const"));
DBUG_RETURN(1);
}
calc_group_buffer(this, group_list);
}
@ -6415,6 +6437,8 @@ remove_const(JOIN *join,ORDER *first_order, COND *cond,
*simple_order=0; // Must do a temp table to sort
else if (!(order_tables & not_const_tables))
{
if (order->item[0]->with_subselect)
order->item[0]->val_str(&order->item[0]->str_value);
DBUG_PRINT("info",("removing: %s", order->item[0]->full_name()));
continue; // skip const item
}
@ -11875,7 +11899,7 @@ test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts,
/*
Check if GROUP BY/DISTINCT can be optimized away because the set is
Check if GROUP BY/DISTINCT can be optimized away because the set is
already known to be distinct.
SYNOPSIS
@ -11883,7 +11907,7 @@ test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts,
table The table to operate on.
find_func function to iterate over the list and search
for a field
DESCRIPTION
Used in removing the GROUP BY/DISTINCT of the following types of
statements:
@ -11894,12 +11918,13 @@ test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts,
then <any combination of a,b,c>,{whatever} is also distinct
This function checks if all the key parts of any of the unique keys
of the table are referenced by a list : either the select list
of the table are referenced by a list : either the select list
through find_field_in_item_list or GROUP BY list through
find_field_in_order_list.
If the above holds then we can safely remove the GROUP BY/DISTINCT,
If the above holds and the key parts cannot contain NULLs then we
can safely remove the GROUP BY/DISTINCT,
as no result set can be more distinct than an unique key.
RETURN VALUE
1 found
0 not found.
@ -11922,7 +11947,8 @@ list_contains_unique_index(TABLE *table,
key_part < key_part_end;
key_part++)
{
if (!find_func(key_part->field, data))
if (key_part->field->maybe_null() ||
!find_func(key_part->field, data))
break;
}
if (key_part == key_part_end)