Commit b8b9738e authored by evgen@moonbone.local's avatar evgen@moonbone.local
Browse files

item_strfunc.cc: 

  Fix for bug#16716 for --ps-protocol mode.
item_cmpfunc.cc:
  Fix for a memory allocation/freeing problem in agg_cmp_type() after fix
for bug#16377. Few language corrections.
parent d22c082b

sql/item_cmpfunc.cc

+11 −21
Original line number Diff line number Diff line
@@ -83,21 +83,21 @@ static void agg_result_type(Item_result *type, Item **items, uint nitems) 
    items will be used for aggregation.

    If there are DATE/TIME fields/functions in the list and no string

    fields/functions in the list then:

      The INT_RESULT type will be used for aggregation instead of orginal

      The INT_RESULT type will be used for aggregation instead of original

      result type of any DATE/TIME field/function in the list

      All constant items in the list will be converted to a DATE/TIME using

      found field or result field of found function.



    Implementation notes:

      The code is equvalent to:

      1. Check the list for presense of a STRING field/function.

      The code is equivalent to:

      1. Check the list for presence of a STRING field/function.

         Collect the is_const flag.

      2. Get a Field* object to use for type coercion

      3. Perform type conversion.

      1 and 2 are implemented in 2 loops. The first searches for a DATE/TIME

      field/function and checks presense of a STRING field/function.

      field/function and checks presence of a STRING field/function.

      The second loop works only if a DATE/TIME field/function is found.

      It checks presense of a STRING field/function in the rest of the list.

      It checks presence of a STRING field/function in the rest of the list.



  TODO

    1) The current implementation can produce false comparison results for
@@ -120,8 +120,9 @@ static void agg_result_type(Item_result *type, Item **items, uint nitems) 
static void agg_cmp_type(THD *thd, Item_result *type, Item **items, uint nitems)

{

  uint i;

  Item::Type res;

  char *buff= NULL;

  Item::Type res= (Item::Type)0;

  /* Used only for date/time fields, max_length = 19 */

  char buff[20];

  uchar null_byte;

  Field *field= NULL;
@@ -147,28 +148,20 @@ static void agg_cmp_type(THD *thd, Item_result *type, Item **items, uint nitems) 
    {

      field= items[i]->tmp_table_field_from_field_type(0);

      if (field)

        buff= alloc_root(thd->mem_root, field->max_length());

      if (!buff || !field)

      {

        if (field)

          delete field;

        if (buff)

          my_free(buff, MYF(MY_WME));

        field= 0;

      }

      else

        field->move_field(buff, &null_byte, 0);

      break;

    }

  }

  if (field)

  {

    /* Check the rest of the list for presense of a string field/function. */

    /* Check the rest of the list for presence of a string field/function. */

    for (i++ ; i < nitems; i++)

    {

      if (!items[i]->const_item() && items[i]->result_type() == STRING_RESULT &&

          !items[i]->result_as_longlong())

      {

        if (res == Item::FUNC_ITEM)

          delete field;

        field= 0;

        break;

      }
@@ -205,10 +198,7 @@ static void agg_cmp_type(THD *thd, Item_result *type, Item **items, uint nitems) 
  }



  if (res == Item::FUNC_ITEM && field)

  {

    delete field;

    my_free(buff, MYF(MY_WME));

  }

}



static void my_coll_agg_error(DTCollation &c1, DTCollation &c2,

sql/item_strfunc.cc

+2 −1
Original line number Diff line number Diff line
@@ -274,7 +274,8 @@ String *Item_func_concat::val_str(String *str) 
  if (!(res=args[0]->val_str(str)))

    goto null;

  use_as_buff= &tmp_value;

  is_const= args[0]->const_item();

  /* Item_subselect in --ps-protocol mode will state it as a non-const */

  is_const= args[0]->const_item() || !args[0]->used_tables();

  for (i=1 ; i < arg_count ; i++)

  {

    if (res->length() == 0)