Commit b63f8f89 authored by gshchepa/uchum@gleb.loc's avatar gshchepa/uchum@gleb.loc
Browse files

Fixed bug #27352. 

The SELECT query with more than 31 nested dependent SELECT queries returned
wrong result.

New error message has been added: ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT.
It will be reported as: "Too high level of nesting for select".
parent 120866c2

mysql-test/r/select.result

+10 −0
Original line number Diff line number Diff line
@@ -3995,4 +3995,14 @@ id select_type table type possible_keys key key_len ref rows Extra 
1	SIMPLE	f1	index	inx	inx	10	NULL	7	Using where; Using index

1	SIMPLE	f2	ref	inx	inx	5	test.f1.b	1	Using where; Using index

DROP TABLE t1;

CREATE TABLE t1 (c1 INT, c2 INT);

INSERT INTO t1 VALUES (1,11), (2,22), (2,22);

EXPLAIN SELECT c1 FROM t1 WHERE (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT COUNT(c2)))))))))))))))))))))))))))))))) > 0;

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where

31	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used

32	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used

EXPLAIN SELECT c1 FROM t1 WHERE (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT (SELECT COUNT(c2))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))) > 0;

ERROR HY000: Too high level of nesting for select

DROP TABLE t1;

End of 5.0 tests

mysql-test/t/select.test

+30 −0
Original line number Diff line number Diff line
@@ -3370,4 +3370,34 @@ EXPLAIN SELECT COUNT(*) FROM t1 f1 INNER JOIN t1 f2 
    WHERE 1 AND f1.b NOT IN (100,2232,3343,51111);

DROP TABLE t1;    



#

# Bug #27352: Incorrect result of nested selects instead of error reporting

#



CREATE TABLE t1 (c1 INT, c2 INT);

INSERT INTO t1 VALUES (1,11), (2,22), (2,22);



let $n= 31;

let $q= COUNT(c2);

while ($n)

{

  let $q= (SELECT $q);

  dec $n;

}

--disable_warnings

eval EXPLAIN SELECT c1 FROM t1 WHERE $q > 0;

--enable_warnings



let $n= 64;

let $q= COUNT(c2);

while ($n)

{

  let $q= (SELECT $q);

  dec $n;

}

--error ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT

eval EXPLAIN SELECT c1 FROM t1 WHERE $q > 0;



DROP TABLE t1;



--echo End of 5.0 tests

sql/share/errmsg.txt

+2 −0
Original line number Diff line number Diff line
@@ -5635,3 +5635,5 @@ ER_NON_INSERTABLE_TABLE 
	eng "The target table %-.100s of the %s is not insertable-into"

ER_ADMIN_WRONG_MRG_TABLE

	eng "Table '%-.64s' is differently defined or of non-MyISAM type or doesn't exist"

ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT

	eng "Too high level of nesting for select"

sql/sql_parse.cc

+5 −0
Original line number Diff line number Diff line
@@ -5889,6 +5889,11 @@ mysql_new_select(LEX *lex, bool move_down) 
  select_lex->init_query();

  select_lex->init_select();

  lex->nest_level++;

  if (lex->nest_level > (int) MAX_SELECT_NESTING)

  {

    my_error(ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT,MYF(0),MAX_SELECT_NESTING);

    DBUG_RETURN(1);

  }

  select_lex->nest_level= lex->nest_level;

  /*

    Don't evaluate this subquery during statement prepare even if

sql/unireg.h

+2 −0
Original line number Diff line number Diff line
@@ -81,6 +81,8 @@ 
                           RAND_TABLE_BIT)

#define MAX_FIELDS	4096			/* Limit in the .frm file */



#define MAX_SELECT_NESTING (sizeof(nesting_map)*8-1)



#define MAX_SORT_MEMORY (2048*1024-MALLOC_OVERHEAD)

#define MIN_SORT_MEMORY (32*1024-MALLOC_OVERHEAD)