Commit d7281b33 authored by unknown's avatar unknown
Browse files

Fix for bug #5595: NULLIF() IS NULL returns false if NULLIF() returns NULL

parent e84eb55a

mysql-test/r/func_if.result

+3 −0
Original line number Diff line number Diff line
@@ -64,3 +64,6 @@ select if(1>2,a,avg(a)) from t1; 
if(1>2,a,avg(a))

1.5000

drop table t1;

SELECT NULLIF(5,5) IS NULL, NULLIF(5,5) IS NOT NULL;

NULLIF(5,5) IS NULL	NULLIF(5,5) IS NOT NULL

1	0

mysql-test/t/func_if.test

+4 −0
Original line number Diff line number Diff line
@@ -47,3 +47,7 @@ insert t1 values (1),(2); 
select if(1>2,a,avg(a)) from t1;

drop table t1;



#

# Bug #5595  NULLIF() IS NULL returns false if NULLIF() returns NULL

#

SELECT NULLIF(5,5) IS NULL, NULLIF(5,5) IS NOT NULL;

sql/item_cmpfunc.cc

+9 −0
Original line number Diff line number Diff line
@@ -654,6 +654,15 @@ Item_func_nullif::val_str(String *str) 
  return res;

}





bool

Item_func_nullif::is_null()

{

  if (!(this->*cmp_func)())

    return null_value=1;

  return 0;

}



/*

  CASE expression 

  Return the matching ITEM or NULL if all compares (including else) failed

sql/item_cmpfunc.h

+1 −0
Original line number Diff line number Diff line
@@ -240,6 +240,7 @@ class Item_func_nullif :public Item_bool_func2 
  void fix_length_and_dec();

  const char *func_name() const { return "nullif"; }

  table_map not_null_tables() const { return 0; }

  bool is_null();

};