Commit 5af4fd25 authored by unknown's avatar unknown
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Bug #11032: getObject() returns a String for a sub-query of type datetime 

 - When returning metadata for scalar subqueries the actual type of the
   column was calculated based on the value type, which limits the actual
   type of a scalar subselect to the set of (currently) 3 basic types : 
   integer, double precision or string. This is the reason that columns
   of types other then the basic ones (e.g. date/time) are reported as
   being of the corresponding basic type.
   Fixed by storing/returning information for the column type in addition
   to the result type.


mysql-test/r/subselect.result:
  Bug #11032: getObject() returns a String for a sub-query of type datetime
   - test case
mysql-test/t/subselect.test:
  Bug #11032: getObject() returns a String for a sub-query of type datetime
   - test case
sql/item_subselect.cc:
  Bug #11032: getObject() returns a String for a sub-query of type datetime
   - store and return the field type as well in addition to result type for 
     single row subqueries
sql/item_subselect.h:
  Bug #11032: getObject() returns a String for a sub-query of type datetime
   - store and return the field type as well in addition to result type for 
     single row subqueries
parent c095f98f

mysql-test/r/subselect.result

+17 −0
Original line number Diff line number Diff line
@@ -2997,3 +2997,20 @@ a a IN (SELECT a FROM t1) 
2	NULL

3	1

DROP TABLE t1,t2;

CREATE TABLE t1 (a DATETIME);

INSERT INTO t1 VALUES ('1998-09-23'), ('2003-03-25');

CREATE TABLE t2 AS SELECT 

(SELECT a FROM t1 WHERE a < '2000-01-01') AS sub_a 

FROM t1 WHERE a > '2000-01-01';

SHOW CREATE TABLE t2;

Table	Create Table

t2	CREATE TABLE `t2` (

  `sub_a` datetime default NULL

) ENGINE=MyISAM DEFAULT CHARSET=latin1

CREATE TABLE t3 AS (SELECT a FROM t1 WHERE a < '2000-01-01') UNION (SELECT a FROM t1 WHERE a > '2000-01-01');

SHOW CREATE TABLE t3;

Table	Create Table

t3	CREATE TABLE `t3` (

  `a` datetime default NULL

) ENGINE=MyISAM DEFAULT CHARSET=latin1

DROP TABLE t1,t2,t3;

mysql-test/t/subselect.test

+16 −0
Original line number Diff line number Diff line
@@ -1965,4 +1965,20 @@ SELECT a, a IN (SELECT a FROM t1) FROM t2; 


DROP TABLE t1,t2;



#

# Bug #11302: getObject() returns a String for a sub-query of type datetime

#

CREATE TABLE t1 (a DATETIME);

INSERT INTO t1 VALUES ('1998-09-23'), ('2003-03-25');



CREATE TABLE t2 AS SELECT 

  (SELECT a FROM t1 WHERE a < '2000-01-01') AS sub_a 

   FROM t1 WHERE a > '2000-01-01';

SHOW CREATE TABLE t2;



CREATE TABLE t3 AS (SELECT a FROM t1 WHERE a < '2000-01-01') UNION (SELECT a FROM t1 WHERE a > '2000-01-01'); 

SHOW CREATE TABLE t3;



DROP TABLE t1,t2,t3;



# End of 4.1 tests

sql/item_subselect.cc

+24 −10
Original line number Diff line number Diff line
@@ -391,6 +391,15 @@ enum Item_result Item_singlerow_subselect::result_type() const 
  return engine->type();

}



/* 

 Don't rely on the result type to calculate field type. 

 Ask the engine instead.

*/

enum_field_types Item_singlerow_subselect::field_type() const

{

  return engine->field_type();

}



void Item_singlerow_subselect::fix_length_and_dec()

{

  if ((max_columns= engine->cols()) == 1)
@@ -1357,31 +1366,35 @@ int subselect_uniquesubquery_engine::prepare() 
  return 1;

}



static Item_result set_row(List<Item> &item_list, Item *item,

			   Item_cache **row, bool *maybe_null)

/* 

 makes storage for the output values for the subquery and calcuates 

 their data and column types and their nullability.

*/ 

void subselect_engine::set_row(List<Item> &item_list, Item_cache **row)

{

  Item_result res_type= STRING_RESULT;

  Item *sel_item;

  List_iterator_fast<Item> li(item_list);

  res_type= STRING_RESULT;

  res_field_type= FIELD_TYPE_VAR_STRING;

  for (uint i= 0; (sel_item= li++); i++)

  {

    item->max_length= sel_item->max_length;

    res_type= sel_item->result_type();

    res_field_type= sel_item->field_type();

    item->decimals= sel_item->decimals;

    *maybe_null= sel_item->maybe_null;

    maybe_null= sel_item->maybe_null;

    if (!(row[i]= Item_cache::get_cache(res_type)))

      return STRING_RESULT; // we should return something

      return;

    row[i]->setup(sel_item);

  }

  if (item_list.elements > 1)

    res_type= ROW_RESULT;

  return res_type;

}



void subselect_single_select_engine::fix_length_and_dec(Item_cache **row)

{

  DBUG_ASSERT(row || select_lex->item_list.elements==1);

  res_type= set_row(select_lex->item_list, item, row, &maybe_null);

  set_row(select_lex->item_list, row);

  item->collation.set(row[0]->collation);

  if (cols() != 1)

    maybe_null= 0;
@@ -1393,13 +1406,14 @@ void subselect_union_engine::fix_length_and_dec(Item_cache **row) 


  if (unit->first_select()->item_list.elements == 1)

  {

    res_type= set_row(unit->types, item, row, &maybe_null);

    set_row(unit->types, row);

    item->collation.set(row[0]->collation);

  }

  else

  {

    bool fake= 0;

    res_type= set_row(unit->types, item, row, &fake);

    bool maybe_null_saved= maybe_null;

    set_row(unit->types, row);

    maybe_null= maybe_null_saved;

  }

}

sql/item_subselect.h

+7 −0
Original line number Diff line number Diff line
@@ -142,6 +142,7 @@ class Item_singlerow_subselect :public Item_subselect 
  longlong val_int ();

  String *val_str (String *);

  enum Item_result result_type() const;

  enum_field_types field_type() const;

  void fix_length_and_dec();



  uint cols();
@@ -273,6 +274,7 @@ class subselect_engine: public Sql_alloc 
  THD *thd; /* pointer to current THD */

  Item_subselect *item; /* item, that use this engine */

  enum Item_result res_type; /* type of results */

  enum_field_types res_field_type; /* column type of the results */

  bool maybe_null; /* may be null (first item in select) */

public:
@@ -282,6 +284,7 @@ class subselect_engine: public Sql_alloc 
    result= res;

    item= si;

    res_type= STRING_RESULT;

    res_field_type= FIELD_TYPE_VAR_STRING;

    maybe_null= 0;

  }

  virtual ~subselect_engine() {}; // to satisfy compiler
@@ -296,6 +299,7 @@ class subselect_engine: public Sql_alloc 
  virtual uint cols()= 0; /* return number of columnss in select */

  virtual uint8 uncacheable()= 0; /* query is uncacheable */

  enum Item_result type() { return res_type; }

  enum_field_types field_type() { return res_field_type; }

  virtual void exclude()= 0;

  bool may_be_null() { return maybe_null; };

  virtual table_map upper_select_const_tables()= 0;
@@ -303,6 +307,9 @@ class subselect_engine: public Sql_alloc 
  virtual void print(String *str)= 0;

  virtual int change_item(Item_subselect *si, select_subselect *result)= 0;

  virtual bool no_tables()= 0;



protected:

  void set_row(List<Item> &item_list, Item_cache **row);

};