Commit d5813a06 authored by unknown's avatar unknown
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Bug#16630: The update fields of the INSERT .. SELECT .. ON DUPLICATE KEY 

UPDATE contains wrong data if the SELECT employs a temporary table.

If the UPDATE values of the INSERT .. SELECT .. ON DUPLICATE KEY UPDATE
statement contains fields from the SELECT part and the select employs a
temporary table then those fields will contain wrong values because they
aren't corrected to get data from the temporary table.

The solution is to add these fields to the selects all_fields list,
to store pointers to those fields in the selects ref_pointer_array and
to access them via Item_ref objects.

The substitution for Item_ref objects is done in the new function called 
Item_field::update_value_transformer(). It is called through the
item->transform() mechanism at the end of the select_insert::prepare()
function.


sql/item.cc:
  Bug#16630: The update fields of the INSERT .. SELECT .. ON DUPLICATE KEY
  UPDATE contains wrong data if the SELECT employs a temporary table.
  The new method Item_field::update_value_transformer() is added. It
  substitutes fields in the update values list for references 
  (Item_ref objects) to them.
sql/item.h:
  Bug#16630: The update fields of the INSERT .. SELECT .. ON DUPLICATE KEY
  UPDATE contains wrong data if the SELECT employs a temporary table.
  The update_value_transformer() method is added to the Item and to the
  Item_field classes.
sql/sql_insert.cc:
  Bug#16630: The update fields of the INSERT .. SELECT .. ON DUPLICATE KEY
  UPDATE contains wrong data if the SELECT employs a temporary table.
  Traverse update values and substitute fields from the select for
  references (Item_ref objects) to them.
sql/sql_select.cc:
  Bug#16630: The update fields of the INSERT .. SELECT .. ON DUPLICATE KEY
  UPDATE contains wrong data if the SELECT employs a temporary table.
  Traverse update values and substitute fields from the select for
  references (Item_ref objects) to them.
mysql-test/r/insert_select.result:
  Added a test case for bug#16630: The update fields of the INSERT .. SELECT ..
  ON DUPLICATE KEY UPDATE contains wrong data if the SELECT employs a 
  temporary table.
mysql-test/t/insert_select.test:
  Added a test case for bug#16630: The update fields of the INSERT .. SELECT ..
  ON DUPLICATE KEY UPDATE contains wrong data if the SELECT employs a 
  temporary table.
parent dd6feec4

mysql-test/r/insert_select.result

+13 −0
Original line number Diff line number Diff line
@@ -731,3 +731,16 @@ select @@identity; 
@@identity

0

drop table t1;

CREATE TABLE t1 (f1 INT, f2 INT );

CREATE TABLE t2  (f1 INT PRIMARY KEY, f2 INT);

INSERT INTO t1 VALUES (1,1),(2,2),(10,10);

INSERT INTO t2 (f1, f2) SELECT f1, f2 FROM t1;

INSERT INTO t2 (f1, f2)

SELECT f1, f1 FROM t2 src WHERE f1 < 2

ON DUPLICATE KEY UPDATE f1 = 100 + src.f1;

SELECT * FROM t2;

f1	f2

101	1

2	2

10	10

DROP TABLE t1, t2;

mysql-test/t/insert_select.test

+15 −0
Original line number Diff line number Diff line
@@ -292,3 +292,18 @@ select @@identity; 
insert ignore t1(f2) select 1;

select @@identity;

drop table t1;



#

# Bug#16630: wrong result, when INSERT t1 SELECT ... FROM t1 ON DUPLICATE

#

CREATE TABLE t1 (f1 INT, f2 INT );

CREATE TABLE t2  (f1 INT PRIMARY KEY, f2 INT);

INSERT INTO t1 VALUES (1,1),(2,2),(10,10);

INSERT INTO t2 (f1, f2) SELECT f1, f2 FROM t1;

INSERT INTO t2 (f1, f2)

  SELECT f1, f1 FROM t2 src WHERE f1 < 2

  ON DUPLICATE KEY UPDATE f1 = 100 + src.f1;

SELECT * FROM t2;

DROP TABLE t1, t2;

sql/item.cc

+45 −0
Original line number Diff line number Diff line
@@ -4809,6 +4809,51 @@ void Item_field::update_null_value() 
}





/*

  Add the field to the select list and substitute it for the reference to

  the field.



  SYNOPSIS

    Item_field::update_value_transformer()

    select_arg      current select



  DESCRIPTION

    If the field doesn't belong to the table being inserted into then it is

    added to the select list, pointer to it is stored in the ref_pointer_array

    of the select and the field itself is substituted for the Item_ref object.

    This is done in order to get correct values from update fields that

    belongs to the SELECT part in the INSERT .. SELECT .. ON DUPLICATE KEY

    UPDATE statement.



  RETURN

    0             if error occured

    ref           if all conditions are met

    this field    otherwise

*/



Item *Item_field::update_value_transformer(byte *select_arg)

{

  SELECT_LEX *select= (SELECT_LEX*)select_arg;

  DBUG_ASSERT(fixed);



  if (field->table != select->context.table_list->table &&

      type() != Item::TRIGGER_FIELD_ITEM)

  {

    List<Item> *all_fields= &select->join->all_fields;

    Item **ref_pointer_array= select->ref_pointer_array;

    int el= all_fields->elements;

    Item_ref *ref;



    ref_pointer_array[el]= (Item*)this;

    all_fields->push_front((Item*)this);

    ref= new Item_ref(&select->context, ref_pointer_array + el,

                      table_name, field_name);

    return ref;

  }

  return this;

}





Item_ref::Item_ref(Name_resolution_context *context_arg,

                   Item **item, const char *table_name_arg,

                   const char *field_name_arg)

sql/item.h

+2 −0
Original line number Diff line number Diff line
@@ -817,6 +817,7 @@ class Item { 
  virtual Item_field *filed_for_view_update() { return 0; }



  virtual Item *neg_transformer(THD *thd) { return NULL; }

  virtual Item *update_value_transformer(byte *select_arg) { return this; }

  virtual Item *safe_charset_converter(CHARSET_INFO *tocs);

  void delete_self()

  {
@@ -1295,6 +1296,7 @@ class Item_field :public Item_ident 
  Item_field *filed_for_view_update() { return this; }

  Item *safe_charset_converter(CHARSET_INFO *tocs);

  int fix_outer_field(THD *thd, Field **field, Item **reference);

  virtual Item *update_value_transformer(byte *select_arg);

  friend class Item_default_value;

  friend class Item_insert_value;

  friend class st_select_lex_unit;

sql/sql_insert.cc

+16 −0
Original line number Diff line number Diff line
@@ -2388,7 +2388,23 @@ select_insert::prepare(List<Item> &values, SELECT_LEX_UNIT *u) 
        next_name_resolution_table=          ctx_state.save_next_local;

    }

    res= res || setup_fields(thd, 0, *info.update_values, 1, 0, 0);

    if (!res)

    {

      /*

        Traverse the update values list and substitute fields from the

        select for references (Item_ref objects) to them. This is done in

        order to get correct values from those fields when the select

        employs a temporary table.

      */

      List_iterator<Item> li(*info.update_values);

      Item *item;



      while ((item= li++))

      {

        item->transform(&Item::update_value_transformer,

                        (byte*)lex->current_select);

      }

    }

    /* Restore the current context. */

    ctx_state.restore_state(context, table_list);

  }