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BUG#15872: Don't run the range analyzer on "t1.keypart NOT IN (const1, ..., )", as that consumes

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too much memory. Instead, either create the equvalent SEL_TREE manually, or create only two ranges that
strictly include the area to scan
(Note: just to re-iterate: increasing NOT_IN_IGNORE_THRESHOLD will make optimization run slower for big 
IN-lists, but the server will not run out of memory. O(N^2) memory use has been eliminated)


mysql-test/r/func_in.result:
  Testcase for BUG#15872
mysql-test/t/func_in.test:
  Testcase for BUG#15872
sql/item.cc:
  BUG#15872: Added Item_decimal::set_decimal_value()
sql/item.h:
  UG#15872: Added Item_decimal::set_decimal_value()
sql/item_cmpfunc.h:
  BUG#15872: Added in_vector::create_item(), in_vector::value_to_item() and their implementations in concrete
  classes.
sql/opt_range.cc:
  BUG#15872: Don't run the range analyzer on "t1.keypart NOT IN (const1, ..., )", as that 
  consumes too much memory. Instead, either 
   A) create the equivalent SEL_TREE manually, making use of the fact that item_not_in->array
      has an ordered IN-list, or
   B) create only two ranges: (-inf|NULL) < X < min_value_from_in_list,  max_value_from_in_list < X
  (Choose #B if the IN-list has > 10K elements)
This commit is contained in:
unknown
2006-04-25 23:33:31 +04:00
parent 2a138695bf
commit 15e00f1f3d
6 changed files with 364 additions and 14 deletions
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93
sql/opt_range.cc
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@ -3501,17 +3501,92 @@ static SEL_TREE *get_func_mm_tree(PARAM *param, Item_func *cond_func,
if (inv)
{
tree= get_ne_mm_tree(param, cond_func, field,
func->arguments()[1], func->arguments()[1],
cmp_type);
if (tree)
/*
We get here for conditions like "t.keypart NOT IN (....)".
If the IN-list contains only constants (and func->array is an ordered
array of them), we construct the appropriate SEL_ARG tree manually,
because constructing it using the range analyzer (as
AND_i( t.keypart != c_i)) will cause lots of memory to be consumed
(see BUG#15872).
*/
if (func->array && func->cmp_type != ROW_RESULT)
{
Item **arg, **end;
for (arg= func->arguments()+2, end= arg+func->argument_count()-2;
arg < end ; arg++)
/*
Create one Item_type constant object. We'll need it as
get_mm_parts only accepts constant values wrapped in Item_Type
objects.
We create the Item on param->mem_root which points to
per-statement mem_root (while thd->mem_root is currently pointing
to mem_root local to range optimizer).
*/
MEM_ROOT *tmp_root= param->mem_root;
param->thd->mem_root= param->old_root;
Item *value_item= func->array->create_item();
param->thd->mem_root= tmp_root;
if (!value_item)
break;
/* Get a SEL_TREE for "-inf < X < c_0" interval */
func->array->value_to_item(0, value_item);
tree= get_mm_parts(param, cond_func, field, Item_func::LT_FUNC,
value_item, cmp_type);
if (!tree)
break;
#define NOT_IN_IGNORE_THRESHOLD 1000
SEL_TREE *tree2;
if (func->array->count < NOT_IN_IGNORE_THRESHOLD)
{
tree= tree_and(param, tree, get_ne_mm_tree(param, cond_func, field,
*arg, *arg, cmp_type));
for (uint i=1; i < func->array->count; i++)
{
if (func->array->compare_elems(i, i-1))
{
/* Get a SEL_TREE for "-inf < X < c_i" interval */
func->array->value_to_item(i, value_item);
tree2= get_mm_parts(param, cond_func, field, Item_func::LT_FUNC,
value_item, cmp_type);
/* Change all intervals to be "c_{i-1} < X < c_i" */
for (uint idx= 0; idx < param->keys; idx++)
{
SEL_ARG *new_interval;
if ((new_interval= tree2->keys[idx]))
{
SEL_ARG *last_val= tree->keys[idx]->last();
new_interval->min_value= last_val->max_value;
new_interval->min_flag= NEAR_MIN;
}
}
tree= tree_or(param, tree, tree2);
}
}
}
else
func->array->value_to_item(func->array->count - 1, value_item);
/*
Get the SEL_TREE for the last "c_last < X < +inf" interval
(value_item cotains c_last already)
*/
tree2= get_mm_parts(param, cond_func, field, Item_func::GT_FUNC,
value_item, cmp_type);
tree= tree_or(param, tree, tree2);
}
else
{
tree= get_ne_mm_tree(param, cond_func, field,
func->arguments()[1], func->arguments()[1],
cmp_type);
if (tree)
{
Item **arg, **end;
for (arg= func->arguments()+2, end= arg+func->argument_count()-2;
arg < end ; arg++)
{
tree= tree_and(param, tree, get_ne_mm_tree(param, cond_func, field,
*arg, *arg, cmp_type));
}
}
}
}