Commit 56426fca authored by unknown's avatar unknown
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A fix (bug #10404: select 0/0 returns 0). 


strings/decimal.c:
  A fix (bug #10404: select 0/0 returns 0).
  We should check the second argument (0?) first.
parent e5670bf2

mysql-test/r/type_newdecimal.result

+4 −0
Original line number Diff line number Diff line
@@ -842,3 +842,7 @@ drop table Sow6_2f; 
select 10.3330000000000/12.34500000;

10.3330000000000/12.34500000

0.83701903604698258

set sql_mode='';

select 0/0;

0/0

NULL

mysql-test/t/type_newdecimal.test

+7 −0
Original line number Diff line number Diff line
@@ -869,3 +869,10 @@ drop table Sow6_2f; 
# bug#9501

#

select 10.3330000000000/12.34500000;



#

# Bug #10404

#



set sql_mode='';

select 0/0;

strings/decimal.c

+13 −13
Original line number Diff line number Diff line
@@ -1945,6 +1945,18 @@ static int do_div_mod(decimal_t *from1, decimal_t *from2, 
  sanity(to);



  /* removing all the leading zeroes */

  i= ((prec2 - 1) % DIG_PER_DEC1) + 1;

  while (prec2 > 0 && *buf2 == 0)

  {

    prec2-= i;

    i= DIG_PER_DEC1;

    buf2++;

  }

  if (prec2 <= 0) /* short-circuit everything: from2 == 0 */

    return E_DEC_DIV_ZERO;

  for (i= (prec2 - 1) % DIG_PER_DEC1; *buf2 < powers10[i--]; prec2--) ;

  DBUG_ASSERT(prec2 > 0);



  i=((prec1-1) % DIG_PER_DEC1)+1;

  while (prec1 > 0 && *buf1 == 0)

  {
@@ -1960,19 +1972,6 @@ static int do_div_mod(decimal_t *from1, decimal_t *from2, 
  for (i=(prec1-1) % DIG_PER_DEC1; *buf1 < powers10[i--]; prec1--) ;

  DBUG_ASSERT(prec1 > 0);



  i=((prec2-1) % DIG_PER_DEC1)+1;

  while (prec2 > 0 && *buf2 == 0)

  {

    prec2-=i;

    i=DIG_PER_DEC1;

    buf2++;

  }

  if (prec2 <= 0) /* short-circuit everything: from2 == 0 */

    return E_DEC_DIV_ZERO;



  for (i=(prec2-1) % DIG_PER_DEC1; *buf2 < powers10[i--]; prec2--) ;

  DBUG_ASSERT(prec2 > 0);



  /* let's fix scale_incr, taking into account frac1,frac2 increase */

  if ((scale_incr-= frac1 - from1->frac + frac2 - from2->frac) < 0)

    scale_incr=0;
@@ -2723,6 +2722,7 @@ int main() 
  test_dv("123", "0.01","12300.000000000", 0);

  test_dv("120", "100000000000.00000","0.000000001200000000", 0);

  test_dv("123", "0","", 4);

  test_dv("0", "0", "", 4);

  test_dv("-12193185.1853376", "98765.4321","-123.456000000000000000", 0);

  test_dv("121931851853376", "987654321","123456.000000000", 0);

  test_dv("0", "987","0", 0);