Commit 9b358f81 authored by unknown's avatar unknown
Browse files

BUG#26624: high mem usage (crash) in range optimizer 

 - Post-review fixes
parent edd5a859

sql/opt_range.cc

+15 −14
Original line number Diff line number Diff line
@@ -175,7 +175,7 @@ static char is_null_string[2]= {1,0}; 
      Example:

        By induction: Let's take any interval on some keypart in the middle:



           kp15=1 

           kp15=c0

        

        Then let's AND it with this interval 'structure' from preceding and

        following keyparts:
@@ -186,16 +186,16 @@ static char is_null_string[2]= {1,0}; 
 

             kp14     $      kp15      $      kp16

                      $                $

         +---------+  $   +--------+  $   +---------+

         | kp14=c1 |--$-->| kp15=1 |--$-->| kp16=c3 |

         +---------+  $   +--------+  $   +---------+

         +---------+  $   +---------+  $   +---------+

         | kp14=c1 |--$-->| kp15=c0 |--$-->| kp16=c3 |

         +---------+  $   +---------+  $   +---------+

              |       $                $              

         +---------+  $   +--------+  $             

         | kp14=c2 |--$-->| kp15=1 |  $             

         +---------+  $   +--------+  $             

         +---------+  $   +---------+  $             

         | kp14=c2 |--$-->| kp15=c0 |  $             

         +---------+  $   +---------+  $             

                      $                $

                      

       Note that we had to duplicate "kp15=1" and there was no way to avoid

       Note that we had to duplicate "kp15=c0" and there was no way to avoid

       that. 

       The induction step: AND the obtained expression with another "wrapping"

       expression like (*).
@@ -477,7 +477,7 @@ typedef struct st_qsel_param { 
    max_key[MAX_KEY_LENGTH+MAX_FIELD_WIDTH];

  bool quick;				// Don't calulate possible keys

  COND *cond;

  /* Numbr of SEL_ARG objects allocated by SEL_ARG::clone_tree operations */

  /* Number of SEL_ARG objects allocated by SEL_ARG::clone_tree operations */

  uint alloced_sel_args; 

} PARAM;
@@ -681,7 +681,8 @@ SEL_ARG *SEL_ARG::clone(PARAM *param, SEL_ARG *new_parent, SEL_ARG **next_arg) 
    tmp->parent=new_parent;

    tmp->next_key_part=next_key_part;

    if (left != &null_element)

      tmp->left=left->clone(param, tmp, next_arg);

      if (!(tmp->left=left->clone(param, tmp, next_arg)))

	return 0;				// OOM



    tmp->prev= *next_arg;			// Link into next/prev chain

    (*next_arg)->next=tmp;