Commit 2fded7d5 authored by unknown's avatar unknown
Browse files

Fix for bug #9764 (DISTINCT IFNULL truncates data) 


mysql-test/r/create.result:
  test result fixed
mysql-test/r/distinct.result:
  test result fixed
mysql-test/t/distinct.test:
  test case added
sql/item_cmpfunc.cc:
  max_length should be calculated differently for DECIMAL_RESULT and others
parent e595b7ee

mysql-test/r/create.result

+1 −1
Original line number Diff line number Diff line
@@ -434,7 +434,7 @@ d date YES NULL 
e	varchar(1)	NO			

f	datetime	YES		NULL	

g	time	YES		NULL	

h	varbinary(23)	NO			

h	longblob	NO			

dd	time	YES		NULL	

select * from t2;

a	b	c	d	e	f	g	h	dd

mysql-test/r/distinct.result

+8 −0
Original line number Diff line number Diff line
@@ -464,3 +464,11 @@ SELECT DISTINCT html,SUM(rout)/(SUM(rin)+1) as 'prod' FROM t1 GROUP BY rin; 
html	prod

1	0.0000

drop table t1;

create table t1 (id int, dsc varchar(50));

insert into t1 values (1, "line number one"), (2, "line number two"), (3, "line number three");

select distinct id, IFNULL(dsc, '-') from t1;

id	IFNULL(dsc, '-')

1	line number one

2	line number two

3	line number three

drop table t1;

mysql-test/t/distinct.test

+8 −0
Original line number Diff line number Diff line
@@ -332,3 +332,11 @@ CREATE TABLE t1 ( 
INSERT INTO t1 VALUES ('1',1,0);

SELECT DISTINCT html,SUM(rout)/(SUM(rin)+1) as 'prod' FROM t1 GROUP BY rin;

drop table t1;



#

# Bug 9784 DISTINCT IFNULL truncates data

#

create table t1 (id int, dsc varchar(50));

insert into t1 values (1, "line number one"), (2, "line number two"), (3, "line number three");

select distinct id, IFNULL(dsc, '-') from t1;

drop table t1;

sql/item_cmpfunc.cc

+12 −14
Original line number Diff line number Diff line
@@ -1109,12 +1109,14 @@ void Item_func_between::print(String *str) 
void

Item_func_ifnull::fix_length_and_dec()

{

  agg_result_type(&hybrid_type, args, 2);

  maybe_null=args[1]->maybe_null;

  decimals= max(args[0]->decimals, args[1]->decimals);

  max_length= (max(args[0]->max_length - args[0]->decimals,

                   args[1]->max_length - args[1]->decimals) +

               decimals);

  agg_result_type(&hybrid_type, args, 2);

  max_length= (hybrid_type == DECIMAL_RESULT || hybrid_type == INT_RESULT) ?

    (max(args[0]->max_length - args[0]->decimals,

         args[1]->max_length - args[1]->decimals) + decimals) :

    max(args[0]->max_length, args[1]->max_length);



  switch (hybrid_type) {

  case STRING_RESULT:

    agg_arg_charsets(collation, args, arg_count, MY_COLL_CMP_CONV);
@@ -1225,16 +1227,7 @@ Item_func_if::fix_length_and_dec() 
{

  maybe_null=args[1]->maybe_null || args[2]->maybe_null;

  decimals= max(args[1]->decimals, args[2]->decimals);

  if (decimals == NOT_FIXED_DEC)

  {

    max_length= max(args[1]->max_length, args[2]->max_length);

  }

  else

  {

    max_length= (max(args[1]->max_length - args[1]->decimals,

                   args[2]->max_length - args[2]->decimals) +

               decimals);

  }



  enum Item_result arg1_type=args[1]->result_type();

  enum Item_result arg2_type=args[2]->result_type();

  bool null1=args[1]->const_item() && args[1]->null_value;
@@ -1263,6 +1256,11 @@ Item_func_if::fix_length_and_dec() 
      collation.set(&my_charset_bin);	// Number

    }

  }

  max_length=

    (cached_result_type == DECIMAL_RESULT || cached_result_type == INT_RESULT) ?

    (max(args[1]->max_length - args[1]->decimals,

         args[2]->max_length - args[2]->decimals) + decimals) :

    max(args[1]->max_length, args[2]->max_length);

}