Commit b779af55 authored by sergefp@mysql.com's avatar sergefp@mysql.com
Browse files

BUG#34945: "ref_or_null queries that are null_rejecting and have a null value crash mysql" 

- Apply Eric Bergen's patch: in join_read_always_key(), move ha_index_init() call
  to before the late NULLs filtering code.
- Backport function comments from 6.0.
parent fc1ae077

mysql-test/r/null_key.result

+18 −0
Original line number Diff line number Diff line
@@ -429,3 +429,21 @@ Handler_read_prev 0 
Handler_read_rnd	0

Handler_read_rnd_next	5

DROP TABLE t1,t2,t3,t4;

CREATE TABLE t1 (

a int(11) default NULL,

b int(11) default NULL,

KEY a (a,b)

);

INSERT INTO t1 VALUES (0,10),(0,11),(0,12);

CREATE TABLE t2 (

a int(11) default NULL,

b int(11) default NULL,

KEY a (a)

);

INSERT INTO t2 VALUES (3,NULL),(3,11),(3,12);

SELECT * FROM t2 inner join t1 WHERE ( t1.a = 0 OR t1.a IS NULL) AND t2.a = 3 AND t2.b = t1.b;

a	b	a	b

3	11	0	11

3	12	0	12

drop table t1, t2;

End of 5.0 tests

mysql-test/t/null_key.test

+23 −0
Original line number Diff line number Diff line
@@ -240,3 +240,26 @@ SHOW STATUS LIKE "handler_read%"; 


DROP TABLE t1,t2,t3,t4;

# End of 4.1 tests



#

# BUG#34945 "ref_or_null queries that are null_rejecting and have a null value crash mysql"

# 

CREATE TABLE t1 (

  a int(11) default NULL,

  b int(11) default NULL,

  KEY a (a,b)

);

INSERT INTO t1 VALUES (0,10),(0,11),(0,12);



CREATE TABLE t2 (

  a int(11) default NULL,

  b int(11) default NULL,

  KEY a (a)

);

INSERT INTO t2 VALUES (3,NULL),(3,11),(3,12);



SELECT * FROM t2 inner join t1 WHERE ( t1.a = 0 OR t1.a IS NULL) AND t2.a = 3 AND t2.b = t1.b;



drop table t1, t2;

-- echo End of 5.0 tests

sql/sql_select.cc

+26 −3
Original line number Diff line number Diff line
@@ -11173,19 +11173,42 @@ join_read_key(JOIN_TAB *tab) 
}





/*

  ref access method implementation: "read_first" function



  SYNOPSIS

    join_read_always_key()

      tab  JOIN_TAB of the accessed table



  DESCRIPTION

    This is "read_fist" function for the "ref" access method.

   

    The functon must leave the index initialized when it returns.

    ref_or_null access implementation depends on that.



  RETURN

    0  - Ok

   -1  - Row not found 

    1  - Error

*/



static int

join_read_always_key(JOIN_TAB *tab)

{

  int error;

  TABLE *table= tab->table;



  /* Initialize the index first */

  if (!table->file->inited)

    table->file->ha_index_init(tab->ref.key);



  /* Perform "Late NULLs Filtering" (see internals manual for explanations) */

  for (uint i= 0 ; i < tab->ref.key_parts ; i++)

  {

    if ((tab->ref.null_rejecting & 1 << i) && tab->ref.items[i]->is_null())

        return -1;

  }

  if (!table->file->inited)

    table->file->ha_index_init(tab->ref.key);



  if (cp_buffer_from_ref(tab->join->thd, &tab->ref))

    return -1;

  if ((error=table->file->index_read(table->record[0],